1 . 听下面一段独白，回答以下小题。
1. What is the percentage of persons aged 60 and over now in industrialized nations?

A．4%—8%.

B．13%—20%.

C．10%—20%.

2. What should we do for old people?

A．We give them more money.

B．We let them live alone.

C．We take good care of them.

3. Why do old people benefit us?

A．Because they are rich in knowledge and experience.

B．Because they don’t need any care.

C．Because they don’t cause any trouble.

4. What does society gain from old people?

A．Fame.

B．Money.

C．A deep sense of history.