Answer:
The answer is - Ann’s user account was not added to the group policy.
Step-by-step explanation:
Group policy is a feature that is used to manage Windows systems and it enables configuration of operating systems and centralized management of settings on client computers and servers that are linked to the domain. It is able to do these through a Group Policy Object (GPO) which contain credentials related settings such as password expiration.
Since Anne was not prompted to change her password then the reason is that her user account was not added to the group policy. Even if a user account has administrator privileges, once the account is added to the group policy it would have to also change password every 15 days which is a requirement of the group policy.