What is the operating principle of detergent type lubricating oil that provides the oil with its unique properties?

Correct Answer: Option A — Detergent and dispersant additives are able to hold solids in suspension.

Detergent and dispersant additives function by surrounding carbonaceous deposits and oxidation products, keeping them suspended in the oil rather than allowing them to agglomerate. This prevents sludge formation on engine surfaces, ensuring contaminants are carried to the filtration system for removal, maintaining internal cleanliness in high-temperature diesel environments.