Which statement is NOT true about the formation of early organisms? A) The first organisms were anaerobic because the atmosphere was devoid of oxygen. B) The original electron donor for photosynthetic processes was probably H₂S. C) Oxygen, a powerful oxidant, was probably welcomed by anaerobic organisms as a preferable choice for metabolic reactions. D) The transfer of electrons to O₂ releases more energy than transferring electrons to SO₄²^- E) Cyanobacteria are modern descendants of early photosynthetic oxygen-producers.

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Anaerobic organisms, which thrived in the early Earth's oxygen-free atmosphere, would have found the appearance of oxygen (a powerful oxidant) in the environment toxic rather than welcoming. Oxygen was detrimental to many anaerobic life forms, leading to what is known as the Great Oxygenation Event, which caused many anaerobes to die out or adapt to new ecological niches.

Which Statement Is NOT True About the Formation of Early