Which statement about synthetic oils is supported by the material?

• A. They extend intervals because they resist soot contamination more than conventional oil
• B. They do not oxidize as quickly as conventional oil
• C. They can be used longer because they resist thinning under heat
• D. They are cheaper than conventional oil

Answer: (B)

The main concept is how oxidation stability differs between synthetic and conventional oils. Oxidation is a chemical reaction that happens with heat and oxygen, producing acids, varnish, and sludge and often changing oil viscosity over time. Synthetic oils use more stable base stocks and stronger antioxidant additives, so they resist reacting with oxygen more effectively than conventional oils. That’s why the statement that they do not oxidize as quickly as conventional oil is the best-supported claim. While synthetic oils can contribute to longer drain intervals and better high-temperature performance, the material most directly supports the idea of slower oxidation. They are not typically cheaper than conventional oils, so the price claim isn’t supported.