One major disadvantage of a low-speed diesel as compared to a steam main- propulsion system is __________.

Correct Answer: Option A — a minimum speed for the engines that limits the minimum speed of the vessel

Direct-drive low-speed diesel engines possess a strict minimum idling RPM to maintain stable combustion and operational reliability. This imposes a corresponding minimum vessel speed, whereas steam turbines and geared configurations can achieve lower continuous propeller shaft speeds for precise maneuvering.