TASK DEFINITION: Given a statement and question, generate the answer to the question such that the answer is contained in the statement.
PROBLEM: statement: an optical system is used for observing stars by researchers, question: What is used for observing stars by researchers?

SOLUTION: an optical system

PROBLEM: statement: Fossils are remnants of ancient forms., question: What are remnants of ancient forms?

SOLUTION: Fossils

PROBLEM: statement: respiration requires a certain amount of carbon dioxide, question: What does respiration require?

SOLUTION:
carbon dioxide