An animal requires energy to move.
And as they move or run, their legs barely move.
An animal requires energy to run.
What requires energy?
Options:
[1] trees staying in place
[2] animals with backbones
[3] Veins and arteries.
[4] statues not moving
[5] some invertebrates
[6] rocks remaining still
[7] power stations
[8] animals running