单项选择题

What has happened since the and of the Ice Age

A．Many species have moved further north.
B．Many new species have come into existence.
C．Many species have developed a habit of migration.
D．Many species have become less sensitive to climate.

<上一题目录下一题>

热门试题

单项选择题

Why were the two large jets specially mentioned

A．To show the key role played by the air traffic controller.
B．To show the great responsibility of the pilots.
C．To give an example of air disasters.
D．To show that air travel is far safer than driving a car.

单项选择题

What is the growing danger in air travel according to this passage

A．Crowded air traffic.
B．The large size of airplanes.
C．Mistakes by air traffic controllers.
D．Bad weather.