instruction:
Given a statement and question, generate the answer to the question such that the answer is contained in the statement.
question:
statement: upper arm muscles contracting causes a person 's elbow to elongate, question: What muscle contracting causes a person's elbow to elongate?
answer:
upper arm

question:
statement: pollution contains matter suspended in air, question: What is suspended in the air?
answer:
matter

question:
statement: H2O is needed for all life on the planet., question: What is needed for all life on the planet?
answer:
H2O