Multiple Choice
Refer to the graph showing variations in oxygen levels during Earth's history. 
Based on the graph, what is the most logical conclusion about the abundance of plant life in the time interval about 250 million years ago?
A) Terrestrial plants went completely extinct.
B) The abundance of plant life dropped dramatically around this time.
C) Plants did not experience any major changes during this interval.
D) Plant life became much more abundant during this interval.
E) The most abundant types of plants alive at this time did not perform photosynthesis.
Correct Answer:
Verified
Correct Answer:
Verified
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