The correct answer is B) having the flywheel impart a torque to the starter pinion. In a Bendix drive starting motor, the starting pinion is connected to the starting motor shaft through a Bendix drive mechanism. When the starting motor is engaged, the starting pinion is propelled forward by the motor rotation and meshes with the flywheel. The torque from the rotating flywheel then causes the starting pinion to spin faster than the motor shaft, which forces the pinion to retract and disengage from the flywheel once the engine starts. The other options are incorrect because: A) spring force is not the mechanism that disengages the starting pinion, C) the starting cam rotates to engage the pinion, not disengage it, and D) accumulator pressure is not involved in the Bendix drive disengagement process.