The use of digital signatures:

A. requires the use of a one-time password generator.

B. provides encryption to a message.

C. validates the source of a message.

D. ensures message confidentiality.

Explanation:

The use of a digital signature verifies the identity of the sender, but does not encrypt the whole message, and hence is not enough to ensure confidentiality. A one-time password generator is an option, but is not a requirement for using digital signatures.