Questions 4 to 7 are based on the following conversation. At the end of the conversation, you will be given 20 seconds to answer the questions.
Now listen to the conversation.
What kind of robots does the man refer to

A．Desert Animal.
B．Camel, An Unusual Animal.
C．A Typical Summer Day and Night of Desert.
D．The Importance of Water on Desert.

A．They don’t get rid of flabby arms.
B．They can damage arm muscles.
C．They aren’t acceptable to most people.
D．They can raise one’s blood pressur