Identify the correct order in which a server process must invoke the function calls accept, bind, listen, and recv according to UNIX socket APL

Consider the following statements.

I. TCP connections are full duplex
II. TCP has no option for selective acknowledgment
III. TCP connections are message streams

Which one of the following socket API functions converts an unconnected active TCP socket into a passive socket?

The transport layer protocols used for real time multimedia, file transfer, DNS and email, respectively are