Carbon dioxide is released through_________ processes such as respiration and volcano eruptions and through_______ activities such as deforestation, l

Câu hỏi:

Carbon dioxide is released through_________ processes such as respiration and volcano eruptions and through_______ activities such as deforestation, land use changes, and burning fossil fuels. 

A.
human – natural

B.
natural – human

C.
man-made – ordinary

D.
ordinary – man-made

Đáp án đúng: B