What is two-factor authentication?

Your security administrator has told you that he’s implementing a new security policy that includes two-factor authentication. What is two-factor authentication?

A) Your authentication must contain two pieces of information.

B) Your password must contain at least two types of characters, such as upper-case characters, lower-case characters, numbers, and non-alphanumeric characters.

C) Before you can access a resource, you must login correctly twice in a row.

D) Your password is encrypted twice before it is stored on an authentication server.