A diaphragm clutch uses which of the following?

A diaphragm clutch employs a single diaphragm spring rather than multiple coil springs or wide release levers. The diaphragm spring is a key component that provides the necessary clamping force to engage the clutch. This design simplifies the construction of the clutch while effectively distributing the clamping load and allowing for smoother engagement and disengagement.

In contrast, the options referring to multiple coil springs or wide release levers would be characteristic of other types of clutch designs, such as a traditional coil spring clutch, which uses multiple individual springs to provide pressure. Understanding the construction and operation of different clutch types is crucial for recognizing how they function, especially in manual transmission systems.