Basics of cryptography – UGC NET Question

Statements A, B and C accurately summarise core ideas of cryptography, encryption and decryption. They show how information is transformed and restored using algorithms and keys. Statement D is dangerously false because private keys must be kept secret; sharing them openly destroys security. Thus, the correct answer is the combination A, B and C only.

Option A:
Option A is incorrect because it lists only A and B as correct, leaving out C. Statement C is also correct, since decryption reverses encryption to recover plaintext. Excluding C gives an incomplete picture of the cryptographic process.

Option B:
Option B is incorrect because it groups A, C and D as correct, thereby accepting D. Statement D contradicts the requirement to keep private keys secret and would compromise secure communication.

Option C:
Option C is correct because it recognises that protecting, encrypting and decrypting data are the three linked components specified in A, B and C. It excludes the unsafe recommendation in D.

Option D:
Option D is incorrect because it includes B, C and D only, omitting A and accepting D. This both weakens the conceptual definition and endorses insecure behaviour.