You are the administrator of an Active Directory domain. All servers run Windows Server 2003. All client computers run Windows XP Professional. All computers are members of the domain.   The Secure Server （Require Security） IPSec policy is assigned to a file server named Server6. The policy is configured as shown in the exhibit. （Click the Exhibit button.）   Users report that they cannot access shared folders on Server6. Users were able to access shared folders on Server6 prior to the implementation of the IPSec policy.   You need to ensure that all client computers in the domain can access the shared folders on Server6. You must ensure that all communications between client computers and Server6 be encrypted. What should you do？（）

• A、On Server6， enable the All ICMP Traffic IP Security rule in the properties of the Secure Server （Require Security） IPSec policy.
• B、On Server6， enable the  IP Security rule in the properties of the Secure Server （Require Security） IPSec policy.
• C、On all client computers， assign the Client （Respond Only） IPSec policy.
• D、On all client computers， install an IPSec communication certificate in the local machine store.