Why Do Cereals Marketers Most Prefer to Have Their Brand

Why do cereals marketers most prefer to have their brand occupy the shelf-space a foot or two below a typical adult's eye-level?

A) Because they know that adults typically look down when they go by the store shelves.
B) Because that shelf-space is the lowest priced space they could occupy.
C) Because it's a lot easier to restock those shelf-spaces.
D) Because they are targeting the children who go shopping with adults.