Questions 17-20 are based on the following dialogue. You now have 20 seconds to read Questions 17-20.

Where is the man going after they finish talking

A．hardly
B．never
C．less
D．reliably

A．Because it is not similar to the spaceships of the previous twenty years.
B．Because it has different designs and is able to return to earth and make further flights.
C．Because it can be used in a variety of ways now.
D．Because it can be used to establish colonies on earth.

A．they are unaware of the consequences of what they are doing
B．they are reluctant to sacrifice their own economic interests
C．time has not yet come for them to put due emphasis on it
D．it is difficult for them to take effective measures