Your network includes a TS Gateway server named TSG1. TSG1 has installed a self- signed servercertificate that it uses for SSL communications. You want to use a computer running ISA Server as an SSL endpoint for TS Gateway connections. Which of the following steps must you take to ensure that ISA Server can communicate with TS Gateway？（）

• A、Enable HTTPS-HTTP bridging between ISA Server and TS Gateway.
• B、Open TCP port 443 on the computer running ISA Server.
• C、Export the SSL certificate of ISA Server to TS Gateway.
• D、Export the SSL certificate of TS Gateway to ISA Server.