Multiple Choice
An iridium-rich layer of clay,glass spherules,and shocked quartz grains strongly suggest that the K-T boundary extinctions were at least in part caused by ________.
A) a long trend of global warming
B) a long trend of global cooling
C) worldwide explosive volcanism
D) the impact of a bolide (meteoroid or comet)
Correct Answer:
Verified
Correct Answer:
Verified
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