Question

which best explains a primary reason for the inability of life to exist in earths early atmosphere? there was insufficient energy from material collisions to change their density. high temperatures during precambrian time caused surface water evaporation. volcanic eruptions and comet collisions added different gases to the atmosphere. available oxygen was used to help create an ozone layer within earths atmosphere.

Explanation:

Early Earth's atmosphere had little free - oxygen. Oxygen is crucial for most life forms. The formation of the ozone layer from available oxygen meant less free oxygen for life processes. High temperatures and gas - adding events like volcanic eruptions and comet collisions were not the primary reasons for the inability of life to exist compared to the lack of free oxygen. Insufficient energy from material collisions to change density is not directly related to life's inability to exist in the early atmosphere.

Answer:

Available oxygen was used to help create an ozone layer within Earth’s atmosphere.