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.

[Q]: Fact: having food has a positive impact on an organism 's health
[A]: Having food has a positive impact on the health of what?

[Q]: Fact: the mantle is located just below Earth 's crust
[A]: Much iron is in?

[Q]: Fact: damming a river can cause a lake to form
[A]:
If a beaver does what it does in order to build its home, then near the river will form?