What do the API and SAE symbols on oil containers indicate?

The API (American Petroleum Institute) and SAE (Society of Automotive Engineers) symbols found on oil containers signify consistent standards of viscosity, performance, and energy conservation. The API symbol indicates that the oil meets specific performance requirements and quality standards set by the organization. This is vital for ensuring that the engine operates efficiently and effectively, as it guarantees that the oil can properly lubricate and protect engine components under varying conditions.

The SAE classification, on the other hand, provides information about the viscosity grades of the oil. This classification helps consumers choose the appropriate oil for their engine based on temperature variations and engine specifications.

Together, these symbols assure consumers that the oil they are purchasing has been evaluated and meets necessary industry standards, making option C the correct choice.