question: Given the fact "a computer controls a robot", what is the answer to "What is essential for a robot to possess to walk up a flight of stairs?"

answer: electricity

question: Given the fact "all living things eliminate waste", what is the answer to "A deer, shark, human and rose share which common activity?"

answer: defecating

question: Given the fact "mining changes an ecosystem", what is the answer to "What does mining change?"

answer: biological environments

question: Given the fact "a rainbow is formed by refraction of light by splitting light into all different colors", what is the answer to "Marbles in the right light make"

answer:
rainbows