TOEFL Listening: TPO-TOEFL阅读TPO - HQ175XDWE3Q3MW5GN$

Why does the author make the statement, "Indeed, there are vast areas of spruce forest without moose"? A. To highlight a fact whose significance the ecologist Herbert Gleason had missed B. To propose the idea that a spruce forest is by itself a superorganism C. To emphasize that moose are not limited to a single kind of environment D. To criticize the idea of a spruce-moose biome