The cylinders labeled "B" and "C" in the illustration are used to __________. Illustration MO-0125

Correct Answer: Option D — supply the force required to shift the engine camshafts axially to reverse engine rotation

Pneumatic servo cylinders on direct-reversing marine diesels use high-pressure control air to shift the camshaft axially, realigning the fuel cam profiles relative to the cam rollers to reverse engine rotation.