The earth's atmosphere consists mainly of nitrogen and oxygen with smaller proportions of other gases such as carbon dioxide. The amount of carbon dioxide in the atmosphere is maintained through a balance between processes such as photosynthesis, respiration and combustion. However this balance is being affected by human activities which are polluting the atmosphere.
The proportion of these gases in the atmosphere is as follows: nitrogen is the most abundant at 78%, oxygen is next at 21%, while others include carbon dioxide at 0.037% and argon at 0.9 % .
The correct answer is A.) however C.) is cellular respiration or the function of the mitochondria. D.) is describing chloroplasts B.) is something concerning DNA and proteins synthesis
I don't know if this helps or not but you would want to know the age of the rock (absolute dating) and from there you will be able to know the age of the fossil and what caused it to die.
