flushing toilets and washing clothes washing clothes and using sink faucets using sink faucets and showering showering and flushing toilets
I gave my students this multiple choice question: Which two activities use most of the water used in an average U.S. household?

Only one answer is correct among these 4 choices:
- flushing toilets and washing clothes
- washing clothes and using sink faucets
- using sink faucets and showering
- showering and flushing toilets

Could you tell me which one is correct?

flushing toilets and washing clothes