Question 272Motor Plants - Assistant Engineer

The correct answer is A) Sludge. Sludge, which is a semi-solid mixture of unburned fuel, water, and other contaminants, can be satisfactorily removed from diesel fuel by centrifuging. Centrifugal force causes the sludge to separate from the fuel, allowing it to be removed. In contrast, other substances like gasoline, fuel oil, and lube oil cannot be effectively removed from diesel fuel through centrifugation. These substances have different densities and properties that make them unsuitable for removal by this method.