What is the meaning of the writ of “prohibition”?

The correct answer is Option (3) → An order preventing a subordinate court from continuing with a case

Prohibition means “to forbid”. The Supreme Court or a High Court issues it to a lower court or tribunal to stop it from going on with a case that is outside its jurisdiction, while the case is still pending. The other three options describe the writs of quo warranto, certiorari and habeas corpus.