Why Is the Absence of Atmospheric Oxygen (O₂) So Important

Why is the absence of atmospheric oxygen (O₂) so important to the Oparin-Haldane hypothesis?

A) Oxygen is corrosive and thus would have degraded many of the metallic compounds on Earth's surface, releasing toxic gasses into the new atmosphere.
B) Oxygen is more reduced than hydrogen gas, methane, or ammonia.
C) Oxygen would have supported microorganisms that promote chemical decay.
D) Oxygen is able to reverse reactions by removing electrons and hydrogen from organic molecules, thus destroying the first organic compounds as quickly as they developed.
E) Oxygen would have caused multiple explosions, converting chemical energy into heat energy and rendering that energy unavailable for driving the synthesis of organic molecules.