TOEFL Listening: ETS-TOEFL听力机经 - 1P3FJPZE77L6NQ38P$

Why does the professor mention a grocery store? A. To help students understand that various species of shorebirds do not actually compete for food. B. To illustrate that humans and shorebirds share some of the same food sources. C. To emphasize the variety in the diet of a particular shorebird species. D. To demonstrate the abundance of food available at feeding sites along the shoreline.