TOEFL Listening: ETS-TOEFL听力机经 - BW843OE6T24OSLIRP$

Why does the professor imply when he says this: A. The size of the grizzly bear population will soon stabilize. B. The future of the polar bear as a distinct species might be at risk. C. Hybridization has already diminished the polar bear population within a short period of time. D. Hybrid species do not adapt well to sudden changes in the environment.