There may not be enough drinking water. There may not be enough water in the water cycle. There may not be enough oxygen for humans to breathe.
I gave my students this multiple choice question: Sheri went on a field trip with her class and saw a stream with floating garbage. How could this pollution affect humans?

Only one answer is correct among these 4 choices:
- There may not be enough drinking water.
- There may not be enough water in the water cycle.
- There may not be enough oxygen for humans to breathe.

Could you tell me which one is correct?

There may not be enough drinking water.