When entering an unattended machinery space to conduct maintenance or a machinery space round, what must be done?

Correct Answer: Option C — The navigational watch officer should be telephoned at agreed to intervals.

Safety protocols for unattended machinery spaces require personnel to maintain communication with the bridge. The navigational watch officer is responsible for the vessel's safety and must be notified at agreed-upon intervals during maintenance rounds to ensure the safety of the individual and the integrity of the machinery space.