单项选择题

Newly- found fossilized tracks in Alaska proved that dinosaurs' migration between Asia and North America took place ________.

A．much earlier than experts previously thought.
B．much later than experts previously thought.
C．after Asia became an independent continent.
D．sometime around 25 million years ago.

<上一题目录下一题>

热门试题

单项选择题

Witmer's research leads people to believe ________.

A．Tyrannosaurus Re had lips and Triceratops had cheeks.
B．dinosaurs might have looked like mammals such as sheep.
C．dinosaurs might not have looked like what we thought.
D．dinosaurs must have looked like birds or crocodiles.

单项选择题

The discovery of dinosaur fossil sites in Bolivia is eciting because of the following reasons ECEPT ________.

A．they are found in a continent other than Asia and North Continent.
B．the largest dinosaurs in the world are found in this discovery.
C．there are some unknown species of dinosaurs found this time.
D．the dinosaurs were believed to be some of the last ones on earth.

相关试题