Your network contains a single Active Directory domain.  A domain controller named DC2 fails.   You need to remove DC2 from Active Directory.   Which two actions should you perform（）

• A、At the command prompt， run dcdiag.exe /fix.
• B、At the command prompt， run netdom.exe remove dc2.
• C、From Active Directory Sites and Services， delete DC2.
• D、From Active Directory Users and Computers， delete DC2.