the ability of farmers to plant crops the ability of scientists to study other planets the ability of Earth to continue recycling rocks the ability of Earth to maintain lower temperatures
I gave my students this multiple choice question: Carbon dioxide emissions have increased due to large numbers of automobiles and increased industrialization. Which of the following has been most affected by the increase in carbon dioxide levels?

Only one answer is correct among these 4 choices:
- the ability of farmers to plant crops
- the ability of scientists to study other planets
- the ability of Earth to continue recycling rocks
- the ability of Earth to maintain lower temperatures

Could you tell me which one is correct?

the ability of Earth to maintain lower temperatures