What type of combustion occurs in a gasoline engine?

The combustion process that occurs in a typical gasoline engine is not homogeneous charge compression ignition (HCCI). Instead, gasoline engines primarily operate on the principle of using a homogeneous air-fuel mixture that is ignited by a spark plug, leading to a rapid combustion event.

HCCI is characterized by the simultaneous ignition of a lean air-fuel mixture in a compressed state without the use of a spark plug, which is not the case in standard gasoline engine operation. The correct answer is found in the combustion process associated with gasoline engines, which includes a homogenous mixture of air and fuel that is compressed until it reaches the temperature required for ignition, typically achieved through a spark ignition system.

Understanding this distinction is crucial for grasping how gasoline engines function in comparison to alternative combustion methods like HCCI or the others listed, which are generally more applicable to different engine types or designs.