The answer is burning coal! Please forgive me if I get this answer wrong!
Answer:
The correct answer is option a-"oceanic lowstand".
Explanation:
An oceanic lowstand is defined as a geological phenomenon at which the sea level is at a low point and the continents are mostly emergent. The Earth has been on onceanic lowstands historically. This has been identified by different evidence, including the Gulf Coast rivers formation of braided channels.
Oxygen, it takes in Carbon Dioxide and releases Oxygen as a waste :)
