Given a fact, create a question that can be answered using the fact. Construct the question such that it is unambiguous, has a unique answer and the answer can be given using the fact.

Fact: baking soda can react chemically with vinegar
Which of the following results from a chemical reaction involving baking soda?

Fact: rain is a source of water
Rain helps?

Fact: magma is found below the ground

You're most likely to encounter magma at?

