Answer:
Due to the earth's rotation and the gravitational pull of the moon.
A. Metabolism this is the process of taking food and making it energy
The Right Answer Is Exoskeleton.
Https://s-media-cache-ak0.pinimg.com/564x/5f/38/fc/5f38fc3ce20c9b6deb0613f73c82e03a.jpg
Here is a image. Hope this helps :)