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.

Input: Consider Input: Fact: Earth 's surface is made of rock

Output: The outer shell of our planet is made of?


Input: Consider Input: Fact: bluebirds live in grassy spaces

Output: Bluebirds are found in?


Input: Consider Input: Fact: skeletal system is made of bones


Output: Which is most considered a part of the skeletal system?