Multiple Choice
In 1980, scientists suggested that the great mass extinction of 65 million years ago (which ended the reign of dinosaurs) may have been caused by a large impact from space. What discovery gives a big boost to this idea?
A) the discovery of some possible traces of life in a meteorite from Mars
B) the discovery of a crater (about a mile across) near Flagstaff, Arizona
C) the discovery of a buried crater (about 200 km across) near Chicxulub, Mexico
D) the discovery of volcanoes on a moon of Jupiter's
E) the discovery of enormous trenches on the ocean floor
Correct Answer:

Verified
Correct Answer:
Verified
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