Breathing is performed by the _____ so that _____ can be replenished and _____ removed from the _____.
Select one:
a. organism as a whole; oxygen; carbon dioxide; cells of an organism
b. cells of an organism; carbon dioxide; oxygen; organism as a whole
c. organism as a whole; carbon dioxide; oxygen; cells of an organism
d. cells of an organism; oxygen; carbon dioxide; organism as a whole