Which of the following is the access level of a user that belongs to both the Administrators and Users groups?

A user with Administrator group membership is not limited to User-level access; the higher privilege of the Administrators group takes effect.

Windows uses an additive permissions model where a user's effective rights are the union of all groups they belong to. Since the Administrators group grants the highest level of system access, membership in both Administrators and Users means the user operates with full Administrator-level privileges. The Users group membership adds no restrictions that would override or reduce the Administrator group rights.

Power User is a separate, distinct Windows group that is not derived from combining Administrators and Users membership; the user in question would be an Administrator, not a Power User.

Remote Desktop User is a separate group that grants only the right to log on via Remote Desktop; it is unrelated to the combined permissions of Administrators and Users.