Question

What is the preferred way of encryption?

(a) pre shared secret key

(b) using key distribution center (KDC)

(c) public key-encryption

(d) symmetric key

I have been asked this question in an international level competition.

The doubt is from Security topic in chapter Security of Operating System

Answer 1

Right choice is (c) public key-encryption

For explanation: Pre Shared key can be compromised and either party can be suspected. Likewise KDC or symmetric key can have breach which are undesirable. Public and private key encryption is a known industry standard.