Earth's primordial atmosphere ____.
A) contained no oxygen
B) was an effective filter that absorbed high-energy ultraviolet rays
C) was mainly oxygen
D) was formed by biological processes

Question

Quizplus · Accepted Answer

Earth's primordial atmosphere did not contain oxygen. Instead, it was mainly composed of nitrogen, water vapor, carbon dioxide, and small amounts of other gases. It was not an effective filter for high-energy ultraviolet rays, which contributed to the formation of complex organic molecules that eventually led to the development of life. This atmosphere was formed by geological processes such as volcanic activity.

Earth's Primordial Atmosphere ____