Giardia is an important waterborne disease. this organism is a select one:

a. virus

b. protozoan

c. bacterium

d. fungus

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.

B.they all live in soil i know biology