it is a.cell because tissues, organs and organisms are larger than a cell so 'a' is the correct answer
Can you elaborate it’s confusing I think it’s consequence tho
Answer:
It will increase the rate of photosynthesis as there will be more carbon dioxide ... however there may be a limiting factor which will limit the rate to keep it constant... Such as the opening if the stomata to receive more CO2 which in turn causes loss of water by transpiration.