The act of requiring two of the three factors to be used in the authentication process refers to:

A.
Two-Factor Authentication

B.
One-Factor Authentication

C.
Bi-Factor Authentication

D.
Double Authentication

Explanation:
Two-Factor Authentication, also known as strong authentication, must include two out of the three
authentication types.
Incorrect Answers:
B: One-Factor Authentication would only include a single authentication type.
C: Bi-Factor Authentication is not a valid authentication term.
D: Double Authentication is not a valid authentication term.

Harris, Shon, All In One CISSP Exam Guide, 6th Edition, McGraw-Hill, 2013, pp. 163