Final answer:
The statement is FALSE as a too-wide armature air gap can harm the magnetic coupling in electric motors, resulting in insufficient torque to start the motor or to run it, potentially preventing an engine from starting. (option B is the correct answer)
Step-by-step explanation:
The statement, "It is highly unlikely that an armature air gap set too wide will prevent an engine from starting and running," is generally considered to be FALSE. In the context of electric motors, the armature air gap is the space between the rotating armature and the stationary part of the motor, such as the stator. If this gap is set too wide, it can harm the magnetic coupling between the armature and the field windings or magnets, which is critical for the creation of torque.
Poor magnetic coupling can result in insufficient torque to start the motor or to run it under load. In the case of an internal combustion engine, an incorrectly set armature air gap in the starter motor could prevent the engine from starting as the starter motor may not be able to produce the necessary force to turn the engine over.