Answer:
A. Methane
C. Carbon dioxide
Step-by-step explanation:
Methane and carbondioxide are the two gases that determine the human impact on air quality because these gases are produced due to human activities. Methane gas is used in homes for cooking and heating purpose while on the other hand, carbondioxide gas is released from burning of fossil fuels in the engine of vehicles and industries for making different products. These two gases greatly affect air quality.