What is the function of the device labeled "3" shown in the illustration? Illustration MO-0111

Correct Answer: Option B — The cooler removes sensible heat from the jacket water.

Jacket water coolers function as heat exchangers designed to transfer thermal energy from the engine's closed-loop cooling water to a secondary medium, typically sea water. This process removes sensible heat, maintaining the engine jacket water within the manufacturer's specified temperature range to prevent overheating and ensure optimal thermal efficiency.