Question

1. which greenhouse gas is the largest contributor to human - caused global warming?

methane (ch₄)
nitrous oxide (n₂o)
carbon dioxide (co₂)
water vapor (h₂o)

Explanation:

Human - activities such as burning fossil fuels (coal, oil, and gas) release large amounts of carbon dioxide. It has a long - term presence in the atmosphere and is the major greenhouse gas contributing to human - caused global warming. Methane, nitrous oxide, and water vapor also contribute, but not as much as carbon dioxide in terms of human - induced global warming.

Answer:

Carbon dioxide ($CO_2$)