Here's a problem to solve: The human body produces motion by changing chemical energy into mechanical energy. Which of these best describes what happens to the energy?

Among the 4 following options, which is the correct answer?

- A: The total amount of energy increases.
 
- B: The total amount of energy is constant.
 
- C: The energy is destroyed through motion.
 
- D: The amount of chemical energy increases.
 