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

statement: An organism that plays a big role as an aquatic autotrophs is:, question: What is an organism that plays a big role in?
aquatic autotrophs

statement: Going from place to place with an automobile necessitates navigation., question: What does going from place to place with an automobile require?
navigation

statement: Stimuli can cause the brain to experience pain., question: Stimuli can cause the brain to experience what?

pain