The correct answer is A) You're stopped on the side of the road with an engine that won't start.
You should use your vehicle's hazard lights in the following situation "You're stopped on the side of the road with an engine that won't start."
You have to be serious and responsible when using your hazard lights. Basically, you use it when you stop your car. The lights indicate other drivers that your car is stopped in the road. This way you warn other drivers that your car is stopped for a good reason. If its the night of the there is no good visible conditions, you have to use your hazard lights.