What do biologists consider when they classify an animal?

Why are small quantities of chlorofluorocarbons so harmful to the ozone layer? a. the chlorofluorocarbons act like ultraviolet radiation causing large amount of ozone to be produced. b. the chlorine from the chlorofluorocarbons reacts with free molecules of oxygen causing a stop in ozone production c. free oxygen atoms can replace the chlorine in chlorine monoxide, releasing a free atom of chlorine which can then recombine with an oxygen atom in ozone, destroying more ozone. d. chlorofluorocarbons absorb ultraviolet radiation, preventing the formation of ozone select the best answer from the choices provided

Which of the following are true about bacteria? select all that apply. bacteria are all around you. bacteria can or harmful. bacteria are multicellular organisms. bacteria can only be found on the human body.

I’m doing some practice exam questions for biology, and i’m not sure how to do these 3 parts to the question.