Which of the following statements defines the term 'axial float' in reference to reduction gears?

Correct Answer: Option D — A pinion is capable of free axial motion, mating with a fixed double helical gear which establishes its position in the gear train.

Axial float permits a double-helical pinion to move freely in the axial direction, allowing it to self-center and balance tooth loads between the left and right-hand helical faces against a fixed mating gear.