All of the following are correct comparisons of anaerobic and aerobic respiration except:
a. aerobic respiration occurs with oxygen and anaerobic respiration occurs without oxygen

b. more energy is produced as a product to be used by organisms in aerobic

c. respiration than anaerobic aerobic respiration is only done by animal cells but anaerobic is done by plant and animal cells

d. carbon dioxide is always produced by aerobic respiration but only sometimes by anaerobic respiration