Lichens, which are capable of initiating ecological succession even on a bare rock, are actually a symbiotic association of

Explanation

Statement a is incorrect: Algae and bacteria alone do not form lichens. Algae can form symbiosis with fungi, not bacteria in this context. Statement b is correct: Lichens are a mutualistic symbiotic association between algae (or cyanobacteria, which play the role of algae) and fungi. The algal partner (phycobiont) performs photosynthesis and provides food. The fungal partner (mycobiont) offers structure, protection, and helps absorb minerals from the substrate. Statement c is incorrect: While fungi and bacteria may form associations in other ecosystems, this is not the definition of lichens. Statement d is incorrect: Mosses are independent bryophytes and not part of lichen structure