Questions 12 to 15 are based on the conservation you have just heard.

A．The relationship between living things and their environment.
B．The relationship between man and his environment.
C．The relationship between man and living things.
D．The relationship between man’s brain and other living things.

A．Because he was too proud to speak to him.
B．Because he was too lazy to say anything.
C．Because he thought they couldn’t be on good terms.
D．Because he was a quiet man.