Your network consists of a single Active Directory domain. All servers run Windows Server 2003 Service Pack 2 (SP2). You have two global groups named Research and ResearchManagers. The Research group contains all users in a department named Research. The ResearchManagers group contains all managers in the Research department. All members of the ResearchManagers group are members of the Research group. You create a shared folder named Research. The permissions for the Research share are shown in the exhibit.(Click the Exhibit button.) You need to modify the share permissions to ensure that only members of the ResearchManagers group can add and modify files over the network. What should you do? （）

• A、Remove the Domain Users group.
• B、Change the permission assigned to the Research group to Allow - Read.
• C、Remove the Research group. Change the Domain Users permission to Allow - Change.
• D、Remove the Research group. Add the ResearchManagers group and assign the group Allow - Change permission.