When driving downhill ensure you have ample space to stop by following distance from the vehicle ahead.

When driving downhill, ensure you have ample space to stop by increasing your following distance from the vehicle ahead.

Explanation:

Driving downhill bears more risk of downwards skidding due to loss of grip or traction. In order to avoid any accidents in such situations, it is advised that the drivers keep their vehicles at amply large distances from each other. By doing that, it can be ensured that the vehicle would get enough space to gain traction and stop before possibly colliding with the vehicle ahead.

Ithink it's a, but i might be wrong