问题：

[单选]

Your network consists of a single Active Directory domain. The functional level of the domain is Windows Server 2008 R2. All servers run Windows Server 2008 R2.  
A corporate security policy requires complex passwords for user accounts that have administrator  privileges.
You need to design a strategy that meets the following requirements：
èEnsures that administrators use complex passwords  
èMinimizes the number of servers required to support the solution
What should you include in your design？（）

A . Implement Network Access Protection （NAP）.
B . Implement Active Directory Rights Management Services （AD RMS）.
C . Create a new Password Settings Object （PSO） for administrator accounts.
D . Create a new child domain in the forest. Move all non-administrator accounts to the new domain.Configure a complex password policy in the root domain.