Your network is configured as shown in the following diagram.You deploy an enterprise certification authority （CA） on the internal network. You also deploy a Microsoft   Online Responder on the internal network.   You need to recommend a secure method for Internet users to verify the validity of individual certificates.   The solution must minimize network bandwidth. What should you recommend？（）

Deploy a subordinate CA on the perimeter network.

Install a stand-alone CA and the Network Device Enrollment Service （NDES） on a server on the perimeter network.

Install a Network Policy Server （NPS） on a server on the perimeter network. Redirect authentication  requests to a server on the internal network.

Install Microsoft Internet Information Services （IIS） on a server on the perimeter network. Configure IIS  to redirect requests to the Online Responder on the internal network.