What should you do?

Domain.com has employed you as a network administrator. The Domain.com network consists of a single Active Directory forest that contains a parent domain as well as a child domain.
The child domain contains two domain controllers named CERTKILLER-DC01 and CERTKILLER- DC02. CERTKILLER-DC01 and CERTKILLER-DC02 are configured to run Windows Serer 2008. You are in the process of migrating the user accounts from the child domain to that of the parent domain. A new company directive states that the child domain is scheduled for decommissioning.
During the course of the day you receive an instruction from the CIO to remove the child domain from the Active Directory forest.
What should you do? (Choose all that apply.)

A.
Your best option would be to have the Domain Controller service on CERTKILLER-DC01 and CERTKILLER-DC02 stopped in the child domain using the Computer Management Console.

B.
Your best option would be to have the Active Directory domain services role uninstalled in the child domain on CERTKILLER-DC01 and CERTKILLER-DC02 using Server Manager.

C.
Your best option would be to have Dcpromo utility executed on CERTKILLER-DC01 and CERTKILLER-DC02 in the child domain that has the individual answer files.

D.
Your best option would be to have the computer accounts for CERTKILLER-DC01 and CERTKILLER-DC02 deleted in the child domain.

Explanation:
Thereafter the trust relationship between the parent domain and the child domain should be removed.