How can your seat belt be beneficial in case of fire or if the car is sinking in water?

• It keeps you conscious so you can get out of the vehicle.
  Explanation:

  "Fire or sinking in water are rare in collisions. If they do happen, the seat belt helps keep you conscious and gives you a chance to get out of the vehicle."
• It keeps you in your seat so you can't get out of your vehicle.
• Both A & B
• It ejects you out of your vehicle.