Finish the following sentence with the best choice: Learn how to do a proper stomach crunch.

Choices:
- Lie on your front with your knees bent and feet flat on the floor, hip-width apart, slowly contract your abdominals, bringing your shoulder blades 2 inches off the floor and you are done.
- Lie on your back with your knees bent and feet flat on the floor, hip-width apart, slowly contract your abdominals, bringing your shoulder blades 2 inches off the floor and you are done.

Answer:
Lie on your back with your knees bent and feet flat on the floor, hip-width apart, slowly contract your abdominals, bringing your shoulder blades 2 inches off the floor and you are done.