_ protocols are used for remote procedure call.Select one or more:a. Secure Shellb. SSLc. Telnetd. TLS

To determine which protocols are used for Remote Procedure Call (RPC), let's evaluate each option:

1. Secure Shell (SSH): SSH is primarily used for secure access to remote computers, allowing command-line login and execution of commands. While not specifically designed for RPC, it can facilitate remote execution of procedures through secure channels. However, it is not central to RPC itself.

2. SSL (Secure Sockets Layer): SSL is a protocol for securing communication over a computer network. It is often used to protect data transmitted over HTTP (as HTTPS) but is not specifically a protocol for RPC. Thus, it is not directly applicable.

3. Telnet: Telnet is a protocol used for text-based communication over the Internet. It does not provide encryption or security features; therefore, it is not suitable for RPC, especially in modern contexts where security is imperative.

4. TLS (Transport Layer Security): TLS is the successor to SSL and is used to secure communications over a computer network. Similar to SSL, TLS can secure RPC communications but does not function as a standalone RPC protocol.

Conclusion

Among the options given, while none are protocol specifically designated for RPC, a. Secure Shell (SSH) and d. TLS can be associated with RPC in terms of facilitating secure communications for remote procedure calls. Therefore, the correct answers are: a and d.