Critical services are running on CKD20， a domain controller. You have completed restructuring the organizational unit hierarchy for the domain and deleted the needless objects. What would you do to perform an offline defragmentation of the Active Directory database on CKD20 while ensuring that the critical services remain online（）

A. Open the Microsoft Management Console （MMC） and stop the Domain Controller service. After that，run the defrag tool
B. Start the domain controller in the Directory Service restore mode and run the Ntdsutil tool
C. Start the domain controller and then use the Defrag tool to start defragmentation
D. Open the MMC and stop the Domain Controller service. After that， run the Ntdsutil tool.
E. All of the above