Given a statement and question, generate the answer to the question such that the answer is contained in the statement.

Input: Consider Input: statement: plants start food chains, question: Plants start what?

Output: food chains

Input: Consider Input: statement: muscles contracting cause a person's arm to straighten, question: What causes a person's arm to straighten?

Output: muscles contracting

Input: Consider Input: statement: Pigeon eggs have hard shells made of calcium carbonate., question: Pigeon eggs have hard shells made of what?
Output: calcium carbonate