A device needs to decrypt traffic and send unencrypted traffic to the web server. Which method should the BIG-IP Administrator use?

SSL Optimization is a broad marketing term for general TLS performance improvements and does not specifically describe terminating encryption before the backend.

SSL Caching stores session ticket data to accelerate TLS session resumption for returning clients, which is unrelated to whether backend traffic is encrypted or plaintext.

SSL Termination ends the encrypted SSL/TLS session at the BIG-IP, offloading the computationally expensive decryption from backend servers. The BIG-IP then communicates with the web server over unencrypted HTTP on the server-side VLAN, which precisely matches the described requirement of sending unencrypted traffic to the web server.

SSL Bridging decrypts traffic at the BIG-IP but then re-encrypts it before forwarding to the web server, so the backend server still receives encrypted traffic - the opposite of the stated requirement.