题目内容：

Questions are based on the following passage.

1.A. 12%. B. 27%. C. 30%. D. 60%.

2.

A. Because their bodies are not strong enough for regular exercises.

B. Because their doctors prevent them from doing too many exercises.

C. Because they spend greater time doing activities requiring little energy.

D. Because they still keep working at older ages.

3.

A. Because it brings enjoyment to the old.

B. Because it makes life colorful.

C. Because it makes the old move more.

D. Because it saves money for the old.