In the context of classical mechanics, an inertial reference frame is a frame of reference in which Newton's laws of motion hold true without the need for additional fictitious forces. Let's analyze the scenarios you mentioned:
(A) A car moving at a constant velocity: In this case, the car is moving at a constant velocity, which means there is no acceleration involved. An inertial reference frame can be attached to the car because the car's motion satisfies Newton's laws of motion without the need for any additional forces.
(B) A car that is accelerating: When a car is accelerating, it means its velocity is changing, and hence, there is an acceleration involved. In this scenario, the car cannot have an inertial reference frame attached to it because the car's motion requires the introduction of fictitious forces, such as the acceleration force and the force due to friction with the ground.
(C) You didn't mention a scenario for option (C). If you provide additional information, I can help you analyze that case as well.
To summarize, a car moving at a constant velocity can have an inertial reference frame attached to it, while a car that is accelerating cannot have an inertial reference frame attached to it without considering additional forces.