A digital signature contains a message digest to:

A. show if the message has been altered after transmission.

B. define the encryption algorithm.

C. confirm the identity of the originator.

D. enable message transmission in a digital format.

Explanation:

The message digest is calculated and included in a digital signature to prove that the message has not been altered. It should be the same value as a recalculation performed upon receipt. It does not define the algorithm or enable the transmission in digital format and has no effect on the identity of the user; it is there to ensure integrity rather than identity.