What effect did the increase in atmospheric oxygen by photosynthetic organisms have onEarth in terms of the geosphere?

Increase in the atmospheric oxygen led to the development of microbe metabolism.

Explanation:

Earth's initial air and seas were without free oxygen, despite the fact that small cyanobacteria were delivering the gas as a side-effect of photosynthesis. At that point, about 2.4 billion years back, oxygen in the climate unexpectedly expanded by around multiple times in only 200 million years.

Atmospheric oxygen resulted from a change to a microbe's metabolism that evolved once, at a specific time in the earth's history

the answer to your question is b

blue stars have the highest surface temp

stellar distances are usually expressed in light-years

the measure of a star's brightness is called magnitude

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