For giving you understanding ; we need Free O2 but Oxygen is also available in H20 right why dont we use it !!
As the early atmosphere was reducing as there was no free oxygen but it was later produced by chemoautotrophic bacteria !! Living thing release O2 in atmosphere thus making it oxidising in nature and then life evolves !!
Carbon dioxide when the fossil fuels is burned
Answer:
Explanation:The Carnian Pluvial Episode (Late Triassic) was a time of global to a major extinction event and might have been the trigger of the spectacular known delta system by area (1,000,000 km2) in Earth history.
Answer:
I think the correct answer is D
I want to say individuals more so than entire populations. That being said it's because the entire populations of living things are able to evolve and move forward through slow evolution.