Which best explains a primary reason for the inability of life to exist in Earth’s early atmosphere?

Earth's early atmosphere was not inhabitable. It was formed of primarily carbon dioxide, nitrogen, and other gases that spewed from the more than active volcanos. The atmosphere wasn't much of an atmosphere at all due to the excess of volcanic activity! This meant there was little to no oxygen for plant and animal life to survive and it was extremely hot. So the primary reason life was unable to exist in early Earth's atmosphere was because of the highly toxic makeup of the air and lack of oxygen/excess of carbon dioxide, which meant little to no life could survive.

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