Which of the following statements is not true concerning mitochondria?
A. It is now widely believed that mitochondria arose from bacteria that invaded the ancient ancestors of plant and animal cells.
B. All cells contain one mitochondria.
C. Mitochondria are the power plants of the cell, providing most of its ATP supply.
D. They contain their own DNA and RNA.
E. Mitochondria are enclosed by two membranes, the outer membrane is smooth and the inner membrane folds inward forming cristae.