While driving in a tunnel you were forced to bring your vehicle to a halt due to a fire. What should you do now?

Your selections are correct. In case of a fire in a tunnel, it is important to first trigger the fire alarm at the emergency call point to alert authorities and enable a rapid response. If it is safe to do so, you should try to extinguish the fire as best you can to prevent it from spreading. Locking your vehicle, as mentioned in answer 3, is not appropriate; instead, you should quickly leave the vehicle and move to a safe area, such as a marked emergency exit. Always prioritize your own safety and the safety of others when responding to emergencies in tunnels.