TOEFL Listening: ETS-TOEFL听力机经 - J25Q18BW18B1S541P$

According to the professor, what are two possible reasons that white-throated sparrows eat corn on Block Island? A. The birds normally eat corn throughout the year. B. The berries that they usually eat are not available. C. The corn provides good nutrition for long flights. D. The birds can easily locate corn growing on farms.