Questions 11 to 18 are based on the conversation you have just heard.

A．It’s Columbus’ pure luck.
B．It proves that the earth is not round.
C．It enriched the American people.
D．It’s one of the biggest lucky mistakes.

A．To teach young athletes how to avoid burnout.
B．To persuade young children not to worry about criticism.
C．To stress the importance of positive reinforcement to children.
D．To discuss the skill of combining criticism with encouragement.