rainfall levels could decrease air temperatures could increase water sources could become polluted caterpillars could become extinct
I gave my students this multiple choice question: Which of these is most likely a result of using pesticides on farm crops?

Only one answer is correct among these 4 choices:
- rainfall levels could decrease
- air temperatures could increase
- water sources could become polluted
- caterpillars could become extinct

Could you tell me which one is correct?

water sources could become polluted