You have an Azure Active Directory (Azure AD) tenant named contoso.com that has a security group named Group1. Group1 is configured for assigned membership. Group1 has 50 members, including 20 guest users.

You need to recommend a solution for evaluating the membership of Group1. The solution must meet the following requirements:

• The evaluation must be repeated automatically every three months.
• Every member must be able to report whether they need to be in Group1.
• Users who report that they do not need to be in Group1 must be removed from Group1 automatically.
• Users who do not report whether they need to be in Group1 must be removed from Group1 automatically.

What should you include in the recommendation?

A. Implement Azure AD Identity Protection.

B. Change the Membership type of Group1 to Dynamic User.

C. Create an access review.

D. Implement Azure AD Privileged Identity Management (PIM).

Explanation:
Have reviews recur periodically: You can set up recurring access reviews of users at set frequencies such as weekly, monthly, quarterly or annually, and the reviewers will be notified at the start of each review. Reviewers can approve or deny access with a friendly interface and with the help of smart recommendations.

Reference:
https://docs.microsoft.com/en-us/azure/active-directory/governance/access-reviews-overview#learn-about-access-reviews