an acid. a base. an element. More information is needed to classify lemon juice.
I gave my students this multiple choice question: Lemon juice turns litmus paper red, is corrosive and tastes sour. Lemon juice is classified as

Only one answer is correct among these 4 choices:
- an acid.
- a base.
- an element.
- More information is needed to classify lemon juice.

Could you tell me which one is correct?

an acid.