cracking open a geode adjusting a microscope spraying water on plants adding salt to boiling water
I gave my students this multiple choice question: During which activity should a student wear a laboratory apron or coat?

Only one answer is correct among these 4 choices:
- cracking open a geode
- adjusting a microscope
- spraying water on plants
- adding salt to boiling water

Could you tell me which one is correct?

adding salt to boiling water