Multiple Choice
Which of the following is true?
A) Humans may have been causing extinctions thousands of years ago,but our impact has recently increased.
B) Humans are responsible for many of the mass extinctions in the geologic record.
C) Humans only began causing extinctions in the past 150 years.
D) Humans have never had significant impact on species extinctions until the past four decades.
E) Humans have been causing extinctions for thousands of years and we are still causing extinctions at about the same rate.
Correct Answer:

Verified
Correct Answer:
Verified
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