acid rain ozone thinning water pollution global warming
I gave my students this multiple choice question: Raising livestock, such as sheep and cattle, results in the production of large amounts of methane gas (CH4). Methane has the same effect in the atmosphere as carbon dioxide (CO2). As more livestock are raised to provide food for humans, what is the most likely effect of the increase in methane?

Only one answer is correct among these 4 choices:
- acid rain
- ozone thinning
- water pollution
- global warming

Could you tell me which one is correct?

global warming