Prokaryotes Probably First Added Significant Quantities of Oxygen into the Atmosphere

Multiple Choice

Prokaryotes probably first added significant quantities of oxygen into the atmosphere when they

A) used carbon dioxide as the source for ions in photosynthesis.
B) used water as the source for ions in photosynthesis.
C) metabolized hydrogen peroxide.
D) metabolized sulfur dioxide.
E) became endosymbionts within eukaryotic cells.