In India, the term “Public Key Infrastructure” is used in the context of

Explanation

A public key infrastructure relies on digital signature technology, which uses public key cryptography. The basic idea is that the secret key of each entity is only known by that entity and is used for signing. This key is called the private key. There is another key derived from it, called the public key, which is used for verifying signatures but cannot be used to sign. This public key is made available to anyone, and is typically included in the certificate document. Therefore, the correct answer is (a).