Gear systems with can have both drive and driven gears on the same shaft. a. an odd number of gears b. an even number of gears c. a compound gear d. an idler

Option A

Explanation:

A series of intermeshing gears is called a gear train.

Intermeshing gears turn in opposing directions.

In a gear train we have a gear  known as the driver and one  known as the follower.

Driver - is the gear that has the  force or motion input.

Follower - is the gear that results  in the force or motion output.

It may be noted that when the number of intermediate gears are odd, the motion of  both the gears (i.e. driver and driven or follower) is in the same direction.

But if the number of intermediate gears are even, the motion of the driven or  follower will be in the opposite direction of the driver