Please choose the correct answer to the question: Robert has only has power downstairs. In order to move the light from downstairs to his upstairs bedroom, he can

Answer1: Just stay in the downstairs rooms Answer2: set up an array of drinking glasses Answer3: set up an array of mirrors Answer4: Unscrew a light bulb downstairs and move it upstairs

Answer format: answer1/answer2/answer3/answer4
Answer: answer3