Which of the following types of diesel engine lubricating oil filtration schemes must be equipped with a bypass relief valve to insure that the engine bearings are not starved of oil if the filter element should become severely restricted or blocked?

Correct Answer: Option C — Full-flow filter

Full-flow filters process the entire volume of oil before it reaches the engine bearings. If the element becomes clogged, a bypass relief valve is mandatory to prevent oil starvation. This safety feature ensures that even if the filter is blocked, the engine continues to receive essential lubrication.