Question

Which is not a source of carbon dioxide gas? Plants, factories, machines, humans

Answer 1

Pretty sure it's Plants since machines and factories are just filled with carbon dioxide gas and us humans are surrounded by gas and basically need carbon dioxide. Hope my statement helps.

Answer 2

The correct answer is option A, Plants

Step-by-step explanation:

Plants are the only species that take up the carbon dioxide and produces oxygen through the process of photosynthesis. They do not release CO2 directly into the environment. While human take up oxygen and produces carbon dioxide which is exhaled out through respiration. The factories and machine uses fossil fuels rich in carbohydrate which on burning produces carbon dioxide as an exhaustive gas.