Answer:
A. more oxygen to enter the atmosphere
Step-by-step explanation:
Photosynthesis is a metabolic process unique to the cells of autotrophic organisms, due to the possession of the CHLOROPHYLL pigments used in trapping light energy from the sun. Photosynthesis is the process of combining carbondioxide (CO2) and water (H2O) using energy of sunlight to produce glucose and release oxygen gas.
Based on the understanding of the photosynthetic process which is similar in all photosynthetic organisms including photosynthetic prokaryotes e.g. cyanobacteria, the presence of the photosynthetic PROKARYOTE will allow more oxygen in the atmosphere.
Note that, oxygen is released during photosynthesis.