听下面一段独白，回答以下小题。
【小题1】What does ASO-S mainly do?

A．Do solar observation.

B．Study Earth's atmosphere.

C．Make weather forecasting.

【小题2】How long will ASO-S stay in orbit at least?

A．Four years.

B．Forty hours.

C．Seventy years.

【小题3】Why is ASO-S so meaningful?

A．It can block the sun's radiation.

B．It may fill China's gap in the field.

C．It is the first solar satellite globally.