Wheel sensor assemblies are comprised of a toothed tone wheel and a pick-up assembly that do not touch each other. A(n) __ must maintain a specific clearance between the two. Select one: a. pin gap b. air gap c. laser beam d. photo cell

The correct answer is b. air gap.<br /><br />In a wheel sensor assembly, the toothed tone wheel and the pick-up assembly do not touch each other. There must be a specific clearance between the two to ensure proper operation. This clearance is known as the air gap.<br /><br />The air gap is the distance between the toothed tone wheel and the pick-up assembly. It is crucial to maintain this gap to ensure accurate detection of the wheel's position and rotation. If the air gap is too small or too large, it can lead to inaccurate readings or even sensor malfunction.<br /><br />The other options, such as pin gap, laser beam, and photo cell, are not directly related to the clearance between the toothed tone wheel and the pick-up assembly in a wheel sensor assembly.