Final answer:
The transfer of the watch on the bridge should not occur until all equipment checks are completed to ensure safety and readiness. This includes a formal communication process and may be necessary even during rough weather or a course change, provided it is done safely.
Step-by-step explanation:
The question relates to nautical procedures and the safe transfer of watchkeeping responsibilities on the bridge of a ship while underway at sea. The transfer of the watch should be performed under conditions that ensure the safety and smooth operation of the ship.
The correct answer is c) Until all equipment checks are completed. Safety protocols dictate that the incoming watchstanding mate should only assume command after verifying that all navigational and operational equipment is functioning correctly. This ensures the mate is fully informed of the current situation and the vessel's readiness. It is also essential to maintain open communication, which includes formally informing the Captain or appropriate personnel of the change in watch.
Transferring watch during rough weather or a course change could be necessary under certain circumstances and is a part of standard maritime operations, provided that the transfer is conducted safely. Thus, the critical factor is ensuring that equipment checks are complete and communication protocols are followed.