Question 148Motor Plants - QMED

The correct answer is C) jacket water temperature is more easily controlled. In a closed fresh water cooling system used with marine diesel engines, the jacket water temperature is more easily controlled compared to an open seawater cooling system. The closed system allows for better regulation of the cooling water temperature, which is important for the optimal performance and efficiency of the diesel engine. The other answer choices are not as relevant - the cooling water temperature differential (A) is not the primary reason, reversible cooling water pumps (B) are not a defining feature, and the need for water treatment (D) is not the main driver for using a closed fresh water cooling system.