What types of throttles are commonly used in small engines?

The correct answer highlights the types of throttles that are commonly found in small engines, which are primarily electronic and mechanical.

Electronic throttles use sensors and actuators to control the engine speed and performance based on demand. This allows for precise adjustments that can enhance fuel efficiency and responsiveness, making them increasingly popular in modern small engines, particularly in automotive applications or high-performance equipment.

Mechanical throttles, on the other hand, utilize physical components such as cables and levers to regulate air and fuel flow into the engine. This type of throttle is often simpler and more traditional, commonly found in lawn mowers, chainsaws, and other small engine machinery.

The other options do not accurately categorize throttle types used in small engines. Pneumatic and hydraulic systems refer more to control mechanisms than throttle types. Cast and stamped relate to materials and manufacturing processes, not specific throttle styles, and manual and automatic typically describe operating formats rather than the throttle control systems themselves.