A password history value of three means which of the following?

A.
Three different passwords are used before one can be reused.

B.
A password cannot be reused once changed for three years.

C.
After three hours a password must be re-entered to continue.

D.
The server stores passwords in the database for three days.

Explanation:
Password History defines the number of unique new passwords a user must use before an old password
can be reused.
Incorrect Answers:
B: Password history is not defined in time, but the number of unique new passwords.
C: Password History tracks previous passwords so as to prevent password reuse, not for the re-entering of
a password.
D: Password History tracks previous passwords so as to prevent password reuse, it does not deal with
password storage.

https://technet.microsoft.com/en-us/library/cc956938.aspx
Stewart, James Michael, CompTIA Security+ Review Guide, Sybex, Indianapolis, 2014, p. 293