What type of authentication may be needed when a stored key and memorized password are not strong enough and additional layers of security is needed?

A.
Mutual

B.
Multi-factor

C.
Biometric

D.
Certificate

Explanation:
Multi-Factor When two or more of these access methods are included as a part of the authentication process, you are implementing a multi-factor system.
Reference: Security + (SYBEX) page 17