Why is the first stage of a large roller coaster usually to take the riders up a large incline assisted by a chain under the roller coaster carts?

A.) To build potential energy which will be turned into kinetic energy throughout the majority of the ride.

B.) To build elastic potential energy which will be transformed throughout the ride.

C.) To build kinetic energy since the ride is starting from rest.

D.) To build suspense, there is no scientific reason.