Which of the following are true about public key encryption?
a. it requires all senders and receivers to have their own public key and their own private key
b. a message encrypted with a person’s public key can only be decrypted with the same person’s private key
c. a public key can be shared with anyone
d. public key encryption is the most common form of encryption for internet communication

Public key encryption is when an encryption is done with two keys. One of the keys is referred to as the public key, while the other is referred to as a private key.

The true statements about the public key are (b) and (c) because:

(c) A user can decide to share his public key with anyone the user wishes to share with. All receiving users can make use of the public key and a matching private key to access the file shared.

(b) There is only one matching and corresponding key to a public key; this key is referred to as the private key. Along with the public key, it is used to access the file.

Hence, (b) and (c) are correct.

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