Question

which atmospheric gas caused the production of cherts?
oxygen
carbon dioxide
water vapor
nitrogen

Explanation:

Cherts are sedimentary rocks. Oxygen in the atmosphere led to biological processes (like the activity of certain organisms) that contributed to the formation of cherts. For example, some organisms can precipitate silica (a main component of cherts) in the presence of oxygen - related metabolic activities. Carbon dioxide, water vapor, and nitrogen do not have such a direct and prominent role in the typical production mechanisms of cherts.

Answer:

oxygen