Which feature is not relevant when establishing a password policy for new users?

When establishing a password policy for new users, the concept of backup codes is not relevant. Backup codes are typically intended for account recovery and are used as a one-time access method if a user cannot access their primary authentication method. These codes serve a different purpose and do not contribute to the password policy itself, which is primarily focused on how users create and manage their passwords.

In contrast, the other options directly impact the security and management of user passwords. Session lifetime refers to how long a user can stay logged into a session before reauthentication is required, which influences the duration of access after password entry. Password complexity requirements dictate how difficult a password must be, ensuring that users create secure passwords that are less vulnerable to attacks. Minimum password age pertains to how soon a user can change their password after setting one, enforcing a policy that prevents users from quickly cycling through passwords to circumvent password complexity or other policies. Each of these components is crucial to maintaining a robust password policy designed to enhance account security for new users.