As a rollercoaster soars down a hill and back up the other side, describe what happens to the potential energy, kinetic energy, and overall mechanical energy.

A. Potential energy increases; kinetic energy decreases; overall mechanical energy is conserved.
B. Potential energy decreases; kinetic energy increases; overall mechanical energy is conserved.
C. Potential energy and kinetic energy both decrease; overall mechanical energy is conserved.
D. Potential energy and kinetic energy both increase; overall mechanical energy is not conserved.