rainfall levels could decrease air temperatures could increase water sources could become polluted caterpillars could become extinct
I am hesitating between 4 options to answer the following question, which option should I choose?
Question: Which of these is most likely a result of using pesticides on farm crops?
Possibilities:
- rainfall levels could decrease
- air temperatures could increase
- water sources could become polluted
- caterpillars could become extinct

water sources could become polluted