select the correct answer. which statement describes a process involved in the evolution of earth’s early…

select the correct answer. which statement describes a process involved in the evolution of earth’s early atmosphere? a. cyanobacteria transformed carbon dioxide in the atmosphere into oxygen during photosynthesis. b. heavier gases escaped through earth’s atmosphere, leaving only lighter gases such as oxygen behind. c. volcanic eruptions produced enough oxygen to create earth’s atmosphere. d. the amount of oxygen in the atmosphere declined due to respiration, or breathing.

select the correct answer. which statement describes a process involved in the evolution of earth’s early atmosphere? a. cyanobacteria transformed carbon dioxide in the atmosphere into oxygen during photosynthesis. b. heavier gases escaped through earth’s atmosphere, leaving only lighter gases such as oxygen behind. c. volcanic eruptions produced enough oxygen to create earth’s atmosphere. d. the amount of oxygen in the atmosphere declined due to respiration, or breathing.

Answer

Answer:

A. Cyanobacteria transformed carbon dioxide in the atmosphere into oxygen during photosynthesis.

Brief Explanations:

Cyanobacteria were early photosynthetic organisms. They used carbon - dioxide and produced oxygen, changing Earth's early atmosphere. Heavier gases don't escape preferentially leaving only lighter ones. Volcanic eruptions mainly released carbon - dioxide, water vapor, and other gases, not enough oxygen to create the atmosphere. Respiration consumes oxygen but in the early atmosphere, photosynthesis by cyanobacteria was key in oxygen production.