Question ID:PT38 S4 Q3 Passage:Journalist: Obviously, though some animals are purely carnivorous, none would survive without plants. But the dependence is mutual. Many plant species would never have come to be had there been no animals to pollinate, fertilize, and broadcast their seeds. Also, plants' photosynthetic activity would deplete the carbon dioxide in Earth's atmosphere were it not constantly being replenished by the exhalation of animals, engine fumes, and smoke from fires, many set by human beings.  Stem:Which one of the following most accurately expresses the main conclusion of the journalist's argument? Correct Answer Choice:EChoice A:The photosynthetic activity of plants is necessary for animal life, but animal life is also necessary for the occurrence of photosynthesis in plants. Choice B:Some purely carnivorous animals would not survive without plants. Choice C:The chemical composition of Earth and its atmosphere depends, at least to some extent, on the existence and activities of the animals that populate Earth. Choice D:Human activity is part of what prevents plants from depleting the oxygen in Earth's atmosphere on which plants and animals alike depend. Choice E:Just as animals are dependent on plants for their survival, plants are dependent on animals for theirs.