Which of these describes a nebula

It is evolution, because we all have some of the same traits like eye color or shape or ears.

4, two dominant and two recessive

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.