What should you do if your brake pedal suddenly sinks to the floor?

Answer: B — Try pumping the brake pedal

If your brake pedal suddenly sinks to the floor, pumping the brake pedal is a wise initial response. This action can help build up brake pressure temporarily, especially if there is a minor leak or issue with the braking system. By pumping the brakes, you might regain enough pressure to slow down or stop the vehicle safely. It's crucial to maintain control of the situation, and this method can provide a brief solution while you assess the problem. The other options would not effectively address the critical situation of losing brake pressure. Continuing to drive without addressing the issue could lead to serious safety risks, while shifting into neutral does not directly aid in stopping the vehicle and could also complicate control. Pulling over immediately is a prudent action to take as well, but if you are in the process of reacting to the brake pedal's failure, attempting to pump the brakes could be the first step in troubleshooting the immediate loss of braking capability.