The public key is used to perform which of the following? (Select THREE).

A.
Validate the CRL

B.
Validate the identity of an email sender

C.
Encrypt messages

D.
Perform key recovery

E.
Decrypt messages

F.
Perform key escrow

Explanation:
B: The sender uses the private key to create a digital signature. The message is, in effect, signed
with the private key. The sender then sends the message to the receiver. The receiver uses the
public key attached to the message to validate the digital signature. If the values match, the
receiver knows the message is authentic.
C: The sender uses the public key to encrypt a message, and the receiver uses the private key to
decrypt the message.
E: You encrypt data with the private key and decrypt with the public key, though the opposite is
much more frequent.
Public-key cryptography, also known as asymmetric cryptography, is a class of cryptographic
protocols based on algorithms that require two separate keys, one of which is secret (or private)
and one of which is public. Although different, the two parts of this key pair are mathematically
linked.