Multiple Choice
The rare element iridium has been implicated in which "ancient health" crisis?
A) poisoning of primitive algae in the Hadean Eon
B) extinction of the woolly mammoths in late Pleistocene time
C) disappearance of Neanderthal man during the early Cenozoic Era
D) extinction of the dinosaurs at the end of the Cretaceous Period
Correct Answer:

Verified
Correct Answer:
Verified
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