Which example illustrates what happens at a convergent boundary?
A. A ship sinks when it is overcome by too many waves.
B. In a curve a car experiences centrifugal force.
C. Two cars collide head-on with each other.
D. Momentum increases when a roller coaster car goes
downhill.

Mitochondria produce atp, a high energy compound. atp is used for all sorts of enzyme-mediated reactions, such as making proteins/nucleotides/etc, certain compounds cross the cell membrane, muscles move, etc.  without this source of energy, a cell will die. it will not be able to repair itself, defend against pathogens, etc.