This roller coaster increases speed as it travels down the track. Which statement describes the energy of the bistockphoto.com/Haven on this section of track?

A. Mechanical energy decreases as the height of the coaster decreases.

B. Gravitational potential energy is stored as the height of the coaster decreases.

C. Kinetic energy is transformed into gravitational potential energy as the speed of the coaster increases.

D. Gravitational potential energy is transformed into kinetic energy as height decreases and speed increases.​