Which SIP feature allows a user to temporarily stop an ongoing call?

The feature that allows a user to temporarily stop an ongoing call is indeed call hold. When a user places a call on hold, the connection is maintained, but the other party is put in a temporary waiting state. This functionality is particularly useful in various scenarios, such as when a user needs to attend to another matter while remaining connected to the original caller.

Call hold typically involves music or a recorded message being played to the caller while they wait, signaling that the call is not terminated and that they will be attended to again shortly. This feature is essential in both personal and professional communications, allowing for greater flexibility during calls without needing to disconnect and redial.

The other options do not fulfill this purpose. Call forwarding directs calls to another number, call blocking prevents certain calls from coming through, and call screening allows users to filter incoming calls based on criteria they set. None of these options provide the ability to pause a conversation temporarily while retaining the connection, making call hold the correct choice.