The forces acting on you are:
That is. There is not need for any other force, cause the car its going at constant speed, so the acceleration its zero, as the net force its mass multiplied by acceleration, the net force is zero.
The forces acting on you are:
That is. Again. The car its slowing down. But, it cant apply a force in you against the direction of movement to slow you down.
As you can't be slowed down, you will go forward at the same speed you had when the car went steady, and will crash against whatever its in front of you.
D)
The friction force, will pull you against the direction of movement, and slow you down will the car slows down.