Sara is sitting in the back seat as her father drives at a constant speed.

girl sitting in carseat with seatbelt on
If Sara's father presses on the brakes quickly slowing the car down, what slows Sara down?
A.
air resistance on the outside of the car
B.
the seat pushing forward on her
C.
air resistance on the inside of the car
D.
her seat belt pulling back on her

D. her seat belt pulling back on her