Your company uses network access protection (NAP) to enforce policies on client computers that connect to the network. Client computers run windows vista. A group Policy is used to configure client computers to obtain updates from WSUS. Company policy requires that updates labeled important and critical must be applied before client computers can access network resources. You need to ensure that client computes meet the company policy requirement. What should you do?（）
- AEnable automatic updates on each client.
- BEnable the security center on each client.
- CQuarantine clients that do not have all available security updates installed.
- DDisconnect the remote connection until the required updates are installed.