The IT department at a small company is revamping its password policies to bolster security. The company wants to ensure employees follow best practices for creating and managing passwords. The department aims to promote a secure environment by implementing password expiration policies. Which method for password management is BEST to promote a secure environment by requiring users to change their passwords after a certain period?

A$.$ Password expiration

B$.$ Password complexity

C$.$ Password reuse prevention

D$.$ Password recovery via email