Answer:
Option A.
Step-by-step explanation:
In the process of photosynthesis, the plant take in carbon dioxide and release oxygen. All organisms that performs respiration take in oxygen and releases carbon dioxide as a by product while all organism that perform photosynthesis (due to the presence of chlorophyll) take in carbon dioxide and releases oxygen as a by product.
The general chemical equation representing photosynthesis is as follows -
6CO2 + 6 H2O + sunlight ------> C6H12O6 + 6 O2
Hence, option A is correct