Which policy prevents a user from choosing a new password that matches any of the last four passwords they used?

• A. Require Reuse Of The Last Four Passwords
• B. Prohibit Reuse Of The Last Four Passwords
• C. Enforce A Password Change Every 30 Days
• D. Log Password Changes In An Audit Trail

Answer: (B)

The main idea is password history enforcement. This policy keeps a record of the user’s recently used passwords and blocks any new password that matches one of the last few you’ve used, in this case the last four. By preventing reuse of recent passwords, it makes it harder for an attacker who has captured or guessed an old password to gain access again, and it pushes users to create genuinely new credentials.

That’s why this choice is the best fit: it explicitly states that reusing any of the last four passwords is prohibited, which is exactly what prevents a new password from matching recent ones. The other options don’t stop reuse of recent passwords: forcing a change every 30 days changes timing but not the reuse restriction; logging changes audits activity but doesn’t prevent reuse; requiring reuse would do the opposite of strengthening security.