TOEFL Reading: ETS-TOEFL阅读机经 - 587O6VVPM76Z0DTXL$

According to paragraph 4, why are mynahs able to learn to make a wide variety of sounds? A. They have the ability to imitate any sound that they are exposed to. B. The frequency with which mynahs travel from one small area to another exposes them to a wide variety of sounds. C. They are exposed in the wild to calls that are very different from each other. D. An acute sense of hearing allows them to listen to and copy many different sounds.