💥UPSC 2026, 2027, 2028 UAP Mentorship (March Batch) + Access XFactor Notes & Microthemes PDF

Type: Prelims Only

  • Horticulture, Floriculture, Commercial crops, Bamboo Production – MIDH, NFSM-CC, etc.

    Wine Production in India

    Note4Students

    From UPSC perspective, the following things are important:

    Prelims level: Viticulture in India

    Why in the News?

    Despite concerns over high tariff rates that India applies on European wine, going up to 150%, Italy sees the Indian market, along with China, as a big window of opportunity for its signature wines.

    Wine Production in India

    About India’s Wine Market

    • Wine accounts for only 2% of India’s alcohol market, while whiskey and beer dominate with 98%.
    • India’s per capita wine consumption is just 9 ml—1/8000th of France’s.
    • The domestic wine market is expanding at 20-30% annually, fueled by urban demand.
    • Mumbai, Goa, Bengaluru, and Delhi-NCR account for 70% of total wine consumption.
    • Goa leads in per capita wine consumption, driven by tourism and relaxed liquor policies.
    • India has 110+ wineries, with Maharashtra and Karnataka leading in production.
    • Sula Vineyards, India’s largest and most popular winery, produces over 1 million cases annually.
    • Events like the Nashik Wine Festival and Bengaluru Wine Festival attract tourists and wine enthusiasts.
    • Vineyard tourism is boosting the rural economy in Nashik and Nandi Hills of Karnataka.

    Viticulture in India 

    • India’s wine industry revival in the 1980s and 1990s led to increased vineyard expansion, making viticulture a key agricultural activity.
    • Nashik, Maharashtra, is known as the “Wine Capital of India”, producing over 80% of the country’s wine.
    • The semi-sandy soil, dry winters, and proximity to major cities like Mumbai and Pune make it ideal for viticulture.
    • The region has over 6,000–7,000 acres of vineyards dedicated to winemaking.
    • Key Wine Regions in India:
      • Nashik, Maharashtra – India’s largest wine-producing region, with optimal conditions for vineyards.
      • Nandi Hills, Karnataka – A cooler climate and high altitude favor premium wine production.
      • Himachal Pradesh & Tamil Nadu – Emerging high-altitude viticulture hubs.
    • Types of Grapes Used in Indian Wines:
      • Red Wine Grapes: Cabernet Sauvignon, Merlot, Shiraz, Pinot Noir.
      • White Wine Grapes: Chardonnay, Sauvignon Blanc, Chenin Blanc.
      • Indian Varieties: Anab-e-Shahi, Bangalore Blue, Thompson Seedless.

    PYQ:

    [2002] Consider the following plants:

    1. Bougainvillea 2. Carnations 3. Cocoa 4. Grapes

     

    Which of these plants are propagated by stem cuttings?

    (a) 1 and 2 (b) 2 and 3 (c) 1 and 4 (d) 2 and 4

    [2006] Consider the following statements:

    1. Caffeine, a constituent of tea and coffee, is a diuretic.

    2. Citric acid is used in soft drinks.

    3. Ascorbic acid is essential for the formation of bones and teeth.

    4. Citric acid is a good substitution for ascorbic acid in our nutrition.

    Which of the statements given above are correct?

    (a) 1 and 2, only (b) 1, 2 and 3, only (c) 3 and 4 only (d) 1, 2, 3 and 4″

     

  • Telecom and Postal Sector – Spectrum Allocation, Call Drops, Predatory Pricing, etc

    [pib] Bharat 6G Alliance

    Note4Students

    From UPSC perspective, the following things are important:

    Prelims level: Bharat 6G Alliance

    Why in the News?

    Prime Minister has released India’s 6G vision “Bharat 6G Vision” document which envisaged India to be a frontline contributor in design, development and deployment of 6G technology by 2030.

    What is the Bharat 6G Alliance (B6GA)?

    • The B6GA is a collaborative platform established to drive India’s leadership in 6G technology.
    • It is an alliance of public and private enterprises, academic institutions, research organizations, and standardization bodies.
    • Objectives of B6GA:
      • Foster Global Collaboration: Partner with international 6G alliances to share knowledge and best practices.
      • Develop India-Centric 6G Use Cases: Identify key industry applications suited to India’s socio-economic landscape.
      • Drive High-Impact Research & Development: Facilitate cutting-edge research in terahertz communications, AI-driven networks, and quantum-enabled security.
      • Standardization & Spectrum Identification: Influence global 6G standards through active participation in International Telecommunication Union (ITU) and World Radiocommunication Conferences (WRC-27).

    Operationalization of 6G Technology:

    The Bharat 6G Project is structured into 2 key phases:

    • Phase 1 (2023-2025):  Focus on:
      • Exploratory research on futuristic telecom technologies.
      • Proof-of-concept testing in research labs.
      • Risky and innovative pathways in wireless communication.
    • Phase 2 (2025-2030): Focus on:
      • Intellectual property (IP) creation for India-led 6G innovations.
      • Deployment of testbeds leading to large-scale commercialization.
    • International Telecom Union (ITU) is evaluating new spectrum bands for 6G:
      • 4400-4800 MHz, 7125-8400 MHz, and 14.8-15.35 GHz.
      • Final decision to be taken at World Radiocommunication Conference 2027 (WRC-27).
    • Currently, 600 MHz to 26 GHz spectrum bands are allocated for IMT (2G-6G) services in India.

    PYQ:

    [2019] With reference to communication technologies, what is/are the difference / differences between LTE (Long-Term Evolution) and VoLTE (Voice over Long-Term Evolution)?

    1. LTE ‘is commonly marketed as 3G and VoLTE is commonly marketed as advanced 3G.

    2. LTE is data-only technology and VoLTE is voice-only technology.

    3. VoLTE requires IP Multimedia Subsystem (IMS) network for voice calls.

    Select the correct answer using the code given below.

    (a) 1 only (b) 2 and 3 only (c) 1 and 3 only (d) Neither 1 nor 2

     

  • Indian Ocean Power Competition

    ‘MAHASAGAR’ vision for Global South

    Note4Students

    From UPSC perspective, the following things are important:

    Prelims level: MAHASAGAR Initiative

    Why in the News?

    PM Modi has unveiled ‘MAHASAGAR’ (Mutual and Holistic Advancement for Security and Growth Across Regions) during his March 2025 visit to Mauritius, outlining India’s expanded vision for security and development across the Global South.

    What is MAHASAGAR?

    • Mahasagar is India’s expanded strategic vision aimed at enhancing security, trade, and development cooperation across the Global South.
    • It builds on India’s SAGAR (Security and Growth for All in the Region) policy, which focused on the Indian Ocean Region (IOR).
    • Three Core Pillars:
    1. Trade for Development: Enhancing economic ties through technology-sharing and trade facilitation.
    2. Capacity Building for Sustainable Growth: Supporting nations with infrastructure, education, and economic partnerships.
    3. Mutual Security for a Shared Future: Strengthening regional security, maritime cooperation, and defense ties.
    • It seeks to address China’s expanding presence in the Indo-Pacific and Indian Ocean by promoting India-led cooperation models.
    • It aims to position India as a champion of the Global South, amplifying their voice in global policymaking (e.g., G20, IORA, BRICS).

    How Mahasagar builds on SAGAR (2015)?

    • India’s SAGAR policy (2015) was a regional framework focused on maritime security and economic cooperation in the Indian Ocean Region (IOR).
    • Mahasagar broadens this vision to global engagement with the Global South.
    SAGAR (2015) Mahasagar (2025)
    Geographic Scope Indian Ocean Region (IOR) Global South, Indo-Pacific, Africa, Latin America
    Focus Areas Maritime security, economic ties, blue economy, regional stability Trade-driven development, technology-sharing, capacity building, global security
    Strategic Partnerships Mauritius, Seychelles, Maldives, Sri Lanka, IOR countries Expands to Africa, ASEAN, Latin America, Pacific Island Nations
    Security & Defense Cooperation Anti-piracy, maritime domain awareness, EEZ protection Joint naval exercises, cyber security, defense partnerships
    Economic & Developmental Focus Blue economy, infrastructure, trade corridors in IOR Technology transfer, concessional loans, trade in local currencies
    Diplomatic Strategy Regional cooperation through IORA, BIMSTEC Voice of the Global South in G20, BRICS, UN initiatives

     

    PYQ:

    [2017] Consider the following in respect of Indian Ocean Naval Symposium (IONS):

    1. Inaugural IONS was held in India in 2015 under the chairmanship of the Indian Navy.

    2. IONS is a voluntary initiative that seeks to increase maritime co-operation among navies of the littoral states of the Indian Ocean Region.

    Which of the statements given above is/are correct?

    (a) 1 only

    (b) 2 only

    (c) Both 1 and 2

    (d) Neither 1 nor 2

     

  • Primary and Secondary Education – RTE, Education Policy, SEQI, RMSA, Committee Reports, etc.

    PM Schools for Rising India (PM SHRI) Scheme

    Note4Students

    From UPSC perspective, the following things are important:

    Prelims level: PM SHRI Scheme

    Why in the News?

    Union Education Minister comment accusing the Tamil Nadu government of being “dishonest” in implementing the PM SHRI scheme caused disruption in the Lok Sabha.

    What is the PM-SHRI Scheme?

    About  
    • Centrally Sponsored Scheme launched in 2022 to upgrade 14,500 schools as model institutions for NEP 2020 implementation.
    • Objective: To create inclusive, nurturing schools with modern infrastructure, holistic education, and competency-based learning.
    Implementation From 2022-23 to 2026-27. After this, states/UTs will maintain the benchmarks achieved. 

    Funding Pattern:

    1. 60:40 (Centre: State/UTs with legislature, except J&K).
    2. 90:10 for Northeastern & Himalayan States, J&K.
    3. 100% Central funding for UTs without legislature. States must sign an MoU with the Centre to participate.
    Key Features
    • Holistic learning: Focus on communication, collaboration, critical thinking. Experiential, inquiry-driven, learner-centred pedagogy.
    • Modern facilities: Smart classrooms, Computer Labs, Integrated Science Labs, Vocational Labs, Atal Tinkering Labs.
    • Green initiatives: Water conservation, waste recycling, energy efficiency.
    • Competency-based assessments linked to real-life applications.
    Eligible Schools Schools managed by Central/State/UT Governments & local bodies. Kendriya Vidyalayas (KVs) & Jawahar Navodaya Vidyalayas (JNVs) (non-project, with permanent buildings).

    School Quality Assessment Framework (SQAF) ensures performance evaluation & institutional excellence.

    Selection Process Challenge Mode (3-stage process):

    • Stage-1: Signing MoU with the Centre.
    • Stage-2: Identifying eligible schools using UDISE+ data.
    • Stage-3: Schools compete to meet selection criteria, verified by States/UTs/KVS/JNV.

    Final selection by Expert Committee headed by the Education Secretary.

     

    PYQ:

    [2017] What is the purpose of ‘Vidyanjali Yojana’?

    1. To enable the famous foreign campuses in India.

    2. To increase the quality of education provided in government schools by taking help from the private sector and the community.

    3. To encourage voluntary monetary contributions from private individuals and organizations so as to improve the infrastructure facilities for primary and secondary schools.

    Select the correct answer using the code given below:

    (a) 2 only (b) 3 only (c) 1 and 2 only (d) 2 and 3 only

     

  • Innovations in Biotechnology and Medical Sciences

    Genetically-Engineered Bananas to Reduce Food Waste

    Note4Students

    From UPSC perspective, the following things are important:

    Prelims level: RNA interference (RNAi)

    Why in the News?

    Scientists at Tropic, a UK-based biotech company, disabled the PPO gene in bananas slowing down the browning process while allowing normal ripening.

    About the Genetically Engineered Bananas

    • Genetically engineered bananas are modified using biotechnology to extend shelf life, resist browning, and enhance durability.
    • These bananas stay yellow for 12 hours after peeling and are less prone to bruising.
    • The modification prevents enzymatic browning, making bananas look fresh for longer without altering their ripening process.
    • The modification targets polyphenol oxidase (PPO), the enzyme responsible for browning.
    • By disabling PPO activity, oxidation of pigments is slowed, delaying the formation of brown spots.

    Gene-Silencing Method Used:

    • RNA interference (RNAi) is used to silence the PPO gene, reducing its activity without affecting overall banana development.
    • RNAi introduces small RNA molecules that block PPO gene expression, preventing the synthesis of the browning enzyme.
    • This method is precise and does not introduce foreign DNA, making it different from traditional genetically modified organisms (GMOs).
    • Gene-editing techniques like CRISPR-Cas9 are also being explored for future crop modifications.

    PYQ:

    [2019] ‘RNA interference (RNAi)’ technology has gained popularity in the last few years. Why?

    1. It is used in developing gene silencing therapies.

    2. It can be used in developing therapies for-the treatment of cancer.

    3. It can be used to develop hormone replacement therapies.

    4. It can be used to produce crop plants that are resistant to viral pathogens.

    Select the correct answer using the code given below:

    (a) 1, 2 and 4 (b) 2 and 3 (c) 1 and 3 (d) 1 and 4 only

     

  • International Space Agencies – Missions and Discoveries

    What are Collisionless Shock Waves?

    Note4Students

    From UPSC perspective, the following things are important:

    Prelims level: Collisionless Shock Waves

    Why in the News?

    A recent study published by Johns Hopkins University (USA) and Northumbria University (UK) reveals how Collisionless Shock Waves act as cosmic accelerators, helping subatomic particles gain ultra-high energy and travel vast distances in space.

    What are Collisionless Shock Waves?

    • Collisionless shock waves are disturbances in plasma (ionized gas) where energy transfer occurs without direct particle collisions, relying instead on electromagnetic forces.
    • They are found in supernova remnants, black hole disks, pulsars, magnetars, and planetary magnetospheres.
    • They act as natural cosmic accelerators, boosting electrons and other charged particles to ultra-high speeds.

    Key Findings from the Study

    • NASA’s MMS, THEMIS, and ARTEMIS missions observed an electron acceleration event near Earth’s bow shock on December 17, 2017.
    • Electrons in Earth’s foreshock region gained 500 keV of energy, reaching 86% of the speed of light, a huge increase from their usual 1 keV.
    • Diffusive shock acceleration (known for producing high-energy cosmic rays) requires electrons to already be moving at 50% of light speed before further acceleration can occur.
    • The study identifies how electrons receive this initial boost, a long-standing astrophysical mystery.
    • Scientists have long assumed that supernova explosions are the primary source of cosmic rays.
    • The recent study suggests that planetary magnetospheres interacting with stellar winds could also contribute to high-energy cosmic rays.

    How Shock Waves accelerate Particles without Collisions?

    • Unlike in solids, liquids, or gases, where energy is transferred via molecular collisions, plasma particles interact through electromagnetic fields.
    • This allows shock waves to accelerate electrons without direct contact.
    • Multi-Stage Acceleration Process:
      1. Plasma waves interact with electrons, imparting initial energy.
      2. Magnetic turbulence in the shock front causes electrons to spiral, further increasing their speed.
      3. Repeated interactions with plasma waves push electrons to relativistic speeds.
    • Role of Earth’s Bow Shock & Foreshock:
      • When the solar wind collides with Earth’s magnetosphere, it forms a shock wave.
      • The foreshock region ahead of this wave is highly turbulent, enabling efficient electron acceleration.

    PYQ:

    [2009] In the year 2008, which one of the following conducted a complex scientific experiment in which sub-atomic particles were accelerated to nearly the speed of light?

    (a) European Space Agency

    (b) European Organization for Nuclear Research (CERN)

    (c) National Aeronautics and Space Administration (NASA)

    (d) National Academy of Sciences, USA

     

  • Defence Sector – DPP, Missions, Schemes, Security Forces, etc.

    India second-largest arms importer after Ukraine

    Note4Students

    From UPSC perspective, the following things are important:

    Prelims level: India's Arms Imports, Make in India

    Why in the News?

    India remained the second-largest arms importer, despite a 9.3% decline in imports between 2015-19 and 2020-24 a/c to the Stockholm International Peace Research Institute (SIPRI) Report.

    About SIPRI

    • The SIPRI is an independent organization established in 1966, based in Stockholm, Sweden, conducting research on conflict, arms control, and disarmament.
    • SIPRI provides comprehensive data on global arms imports, exports, and military expenditures, tracking defense trends and geopolitical conflicts worldwide.
    • It analyzes ongoing wars, nuclear proliferation, cybersecurity threats, and environmental security, offering policy recommendations for international peace and stability.
    • SIPRI publishes flagship reports such as the SIPRI Yearbook, Arms Transfers Database, and Military Expenditure Database, which are widely used by governments, researchers, and policymakers.

    India’s Arms Imports: Trends and Shifts

    • India remained the world’s second-largest arms importer, despite a 9.3% decline in imports from 2015-19 to 2020-24.
    • Russia accounted for 36% of India’s arms imports in 2020-24, significantly LOWER than 55% in 2015-19 and 72% in 2010-14.
    • India has reduced dependence on Russia and increased arms deals with France, the U.S., and Israel.
    • India became France’s largest arms importer (28%), with 36 Rafale fighter jets and six Scorpene submarines already contracted.
    • India is finalizing agreements for 26 Rafale-M jets and three additional Scorpene submarines.

    Global Arms Trade Highlights

    • Ukraine – The Largest Importer: Due to the ongoing war, Ukraine’s arms imports surged nearly 100 times in 2020-24 compared to 2015-19.
      • The U.S. accounted for 45% of Ukraine’s imports, followed by Germany (12%) and Poland (11%).
    • U.S. dominance in exports: The U.S. expanded its global arms market share to 43%, reinforcing its position as the top exporter.
    • Russia’s decline: Russian arms exports fell by 64%, dropping to 7.8% of global exports, behind France (9.6%).
    • European rearmament: European arms imports surged by 155% in response to rising security threats from Russia.
    • Pakistan’s growing imports: Pakistan’s arms imports grew by 61%, with China supplying 81% of its weapons, up from 74% in 2015-19.
    • China’s self-reliance: For the first time since 1990-94, China dropped out of the top 10 arms importers, reflecting its expanding domestic defense industry.
    • Italy’s rise in arms exports: Italy climbed from 10th to 6th place, with a 4.8% share of global arms exports.

    PYQ:

    [2020] What is the significance of Indo-US defence deals over Indo-Russian defence deals? Discuss with reference to stability in the Indo-Pacific region.

     

  • Police Reforms – SC directives, NPC, other committees reports

    Preventive Detention is a ‘Draconian’ measure: SC

    Note4Students

    From UPSC perspective, the following things are important:

    Prelims level: Preventive Detention

    Why in the News?

    The Supreme Court recently ruled against the Preventive Detention of a couple in Nagaland, emphasizing that constitutional safeguards must be strictly followed, and preventive detention cannot override fundamental rights.

    Court’s Key Observations: Preventive Detention as a ‘Draconian Measure’

    • Violation of Rights: The court ruled that depriving individuals of liberty without trial requires strict adherence to legal safeguards.
    • Lack of Justification: Authorities failed to prove that the detainees posed a credible future threat, rendering the detention unjustified.
    • Language Barrier: Detention orders were in English, a language the detainees did not understand, violating their right to be informed in an accessible manner.

    What is Preventive Detention?

    • Preventive detention is the detention of an individual without trial to prevent them from engaging in activities that may threaten national security, public order, or foreign relations.
    • Unlike punitive detention, it aims to prevent future crimes rather than punish past offenses.
    • Under Article 22 of the Constitution, preventive detention is allowed but with safeguards:
      • Time Limit: Maximum three months, extendable only if an Advisory Board (comprising High Court judges) approves.
      • Rights of the Detainee: Must be informed of reasons for detention (unless against public interest) and given the right to challenge it.
      • Judicial Review: Courts can strike down unjustified detentions.
    • Major Preventive Detention Laws:
      • Public Safety Act (PSA), 1978: Used in J&K; detention up to two years.
      • National Security Act (NSA), 1980: Up to one year for threats to national security.
      • Prevention of Illicit Traffic in Narcotic Drugs and Psychotropic Substances Act (PITNDPS Act), 1988: For drug trafficking cases.
      • Conservation of Foreign Exchange and Prevention of Smuggling Activities Act (COFEPOSA), 1974: For economic offenses & smuggling.

    Supreme Court’s Landmark Rulings

    • Ameena Begum Case (2023): Preventive detention is an exception, not a routine measure.
    • Ankul Chandra Pradhan Case (1997): It aims to prevent threats, not punish individuals.
    • Harikisan vs Maharashtra (1962): Detention orders must be in a language the detainee understands.
    • Gold Smuggling Case (2024): Authorities must consider bail conditions before imposing detention.

    PYQ:

    [2021] With reference to India, consider the following statements:

    1. Judicial custody means an accused is in the custody of the concerned magistrate and such an accused is locked up in a police station, not in jail.
    2. During judicial custody, the police officer in charge of the case is not allowed to interrogate the suspect without the approval of the court.

    Which of the statements given above is/are correct?

    (a) 1 only
    (b) 2 only
    (c) Both 1 and 2
    (d) Neither 1 nor 2

     

  • Indian Army Updates

    Exercise Khanjar-XII

    Note4Students

    From UPSC perspective, the following things are important:

    Prelims level: Exercise KHANJAR-XII

    Why in the News?

    The 12th edition of the India-Kyrgyzstan Joint Special Forces Exercise KHANJAR-XII is set to be held in Kyrgyzstan.

    About Exercise KHANJAR-XII

    • KHANJAR-XII is the 12th edition of the India-Kyrgyzstan Joint Special Forces Exercise, aimed at enhancing counter-terrorism and special operations capabilities.
    • It is a bilateral military exercise held annually since 2011, alternately hosted by India and Kyrgyzstan.
    • The 2025 edition is being conducted in Kyrgyzstan.
    • Participants:
      • Indian Contingent: Parachute Regiment (Special Forces).
      • Kyrgyzstan Contingent: Kyrgyz Scorpion Brigade.
    • The primary objective is to strengthen military cooperation, improve joint operational capabilities, and enhance interoperability between the two nations’ Special Forces.

    Key Features:

    • Counter-Terrorism Focus: Training in urban and high-altitude warfare to counter modern security threats.
    • Special Forces Interoperability: Strengthening coordination in joint military operations.
    • Mountain Warfare & Survival Skills: Enhancing operational effectiveness in challenging terrains.
    • Military Technology Exchange: Sharing expertise on weapons systems, surveillance, and intelligence gathering.
    • Reinforcing India’s Central Asia Outreach: Strengthening India’s engagement with Central Asian nations under its Connect Central Asia policy.
  • Hunger and Nutrition Issues – GHI, GNI, etc.

    What is Minimum Dietary Diversity (MDD) Indicator?

    Note4Students

    From UPSC perspective, the following things are important:

    Prelims level: Minimum Dietary Diversity (MDD) Indicator

    Why in the News?

    The United Nations Statistical Commission has introduced a new global indicator on Minimum Dietary Diversity (MDD) to monitor progress towards Sustainable Development Goal (SDG) 2: Zero Hunger.

    About Minimum Dietary Diversity (MDD) Indicator 

    • The MDD indicator measures whether individuals consume a variety of foods within a 24-hour period to assess dietary quality.
    • It tracks progress toward Sustainable Development Goal 2 (Zero Hunger) and helps identify micronutrient deficiencies in populations.
    • It was adopted by the United Nations Statistical Commission at its 56th session (March 4-7, 2025, New York) and developed by Switzerland, FAO, UNICEF, and WHO.
    • The indicator records whether an individual has consumed at least 5 out of 10 food groups in the last 24 hours.
    • It is measured for children (6-23 months old) and women of reproductive age (15-49 years) to ensure adequate nutrition.
    • 10 Food Groups: It monitors intake from grains, white roots and tubers, pulses, nuts and seeds, milk products, meat, poultry and fish, eggs, dark green leafy vegetables, vitamin A-rich fruits and vegetables, and other vegetables and fruits.
    • Significance:
      • It addresses hidden hunger, malnutrition, and non-communicable diseases by promoting nutrient-rich diets.
      • The indicator strengthens long-term diet monitoring and ensures dietary diversity remains a global priority beyond 2030.

    SDG 2: Zero Hunger – The Larger Goal

    • Adopted in 2015, SDG 2 aims to eliminate hunger and promote sustainable agriculture.
    • Recognizes interconnections between food security, rural development, and nutrition.
    • Hunger remains a global crisis:
      • 757 million people faced hunger in 2023 (nearly 10% of the world population).
      • One in nine people worldwide sleeps hungry each night.
      • 20 million people are at immediate risk of famine in South Sudan, Somalia, Yemen, and Nigeria.

     

    PYQ:

    [2016] Which of the following is/are the indicator/indicators used by IFPRI to compute the Global Hunger Index Report?

    1. Undernourishment
    2. Child stunting
    3. Child mortality

    Select the correct answer using the code given below:

    (a) 1 only

    (b) 2 and 3 only

    (c) 1, 2 and 3

    (d) 1 and 3 only