4. All of the above
Braking distance is determined by condition of the braking system, road/weather conditions, road material (rock, asphalt, concrete) and other factors.
A/c to Wikipedia,
Braking distance refers to the distance a vehicle will travel from the point when its brakes are fully applied to when it comes to a complete stop.
It depends upon various factors. They can be (but not limited to):
- Braking system conditions
- Road surface conditions
- Weather conditions
- Type of roads (based on materials)