Questions 11 to 14 are based on the following passage. At the end of the passage , you will be given 20 seconds to answer the questions.
Now listen to the passage. Why is the animal "pigeon" mentioned in the passage
A．To give an example that both human beings and animals can recognize faces. B．To tell how a skilled writer could describe all the features of different people. C．To indicate how pigeons and people look different. D．To show how faces are like fingers.