The correct answer is: B. parabolic
A parabolic camber is the best suited for cement concrete pavements because it provides a smooth and even surface for vehicles to travel on. It also helps to reduce the amount of water that collects on the pavement, which can cause hydroplaning.
A straight line camber is not as effective as a parabolic camber because it does not provide as much support for the weight of the vehicles. This can cause the pavement to crack and deteriorate over time.
An elliptical camber is a combination of a straight line and a parabolic camber. It is not as effective as a parabolic camber because it does not provide as much support for the weight of the vehicles. However, it is more effective than a straight line camber.
In conclusion, the best shape of camber for cement concrete pavements is a parabolic camber. It provides a smooth and even surface for vehicles to travel on, and it helps to reduce the amount of water that collects on the pavement.