Multiple Choice
The first organisms on Earth were most likely
A) autotrophs that obtained energy through the C4 photosynthetic pathway.
B) autotrophs that obtained energy through the CAM photosynthetic pathway.
C) heterotrophs that obtained energy from amino acids and sugars forming spontaneously in the early atmosphere.
D) heterotrophs that obtained energy from CO2 and high-energy nitrogen compounds.
Correct Answer:

Verified
Correct Answer:
Verified
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