Question

which of these statements best describes the relationship between a driving gear and a driven gear?
a a driven gear is used to stop the motion of a driving gear
a driving gear must always be exactly three times the size of the driven gear
there is no relationship between the driving and driven gears
a driving gear provides the power (input) and turns the driven (ouput) gear

Explanation:

A driving gear is the source of motion and power in a gear - system, and it transfers this power to the driven gear which is the output gear. A driven gear is not used to stop a driving gear. There is no fixed ratio like the driving gear must be three times the size of the driven gear. And clearly, there is a relationship between them.

Answer:

A driving gear provides the power (input) and turns the driven (output) gear