ACCORDING TO THE PASSAGE, HOW DID EDISON TEST HIS NEW INVENTION
32. According to the passage, how did Edison test his new invention? A. He made improvements to the machine. B. He used a carbon transmitter. C. He read a children’s rhyme. D. He produced the audience voice. Mark letter A, B, C or D on your answer sheet to indicate the sentence that is closest in meaning to the original sentence in each of the following questions.