Some Cells Contain Large Numbers of Mitochondria While Others Have

Some cells contain large numbers of mitochondria while others have relatively few or none. This suggests that

A) cells with small numbers of mitochondria have a large ATP supply.
B) cells with large numbers of mitochondria have a low energy demand.
C) some cells are older than others.
D) cells with large numbers of mitochondria are short- lived.
E) cells with large numbers of mitochondria have a high energy demand.