Without knowing it, the right and left-handed twins built balance into the world. The plant-eating animals created by the right-handed twin balanced out the meat-eating animals created by the left-handed twin. And so the world thrived, and this was good.

Which statement best describes the purpose of this excerpt?
to describe who created plant- and meat-eating animals
to explain that some animals are good and others are evil
to explain how balance came to exist in the natural world
to describe two different kinds of animals found in the world