Answer:
Option A, oxygen in the atmosphere
Explanation:
The highest level of oxygen reached during this phase of the geological cycle of earth. The oxygen level in Carboniferous period accounted for 35% as compared to 21% of oxygen in the atmosphere in present time.
Due to high oxygen content, the giant and wide varieties of terrestrial animal and plant species evolved. For example – size of insects and carwlies increased, plant became extremely giant, increase in number of tree ferns etc.
Plant cells do not perform respiration, so A,C, and D couldn't be correct but they don't digest either. so gain energy plants go through a light dependent reaction and the Calvin cycle which makes up photosynthesis.
This may sound terrible but less damage in a collision, and also view
I’m pretty sure it’s the refractory period!!
Hope this helps!
