单选题 According to the passage, which of the following is one of the primary factors that led researchers studying hypnosis to compare auditory hallucinations and imagined sounds?

• (A) The high level of realism involved in auditory hallucinations but not in the experience of external sounds
• (B) The fact that both auditory hallucinations and simple imagining are generated by the research subject
• (C) The observed similarities between visual and auditory hallucinations in hypnotized subjects
• (D) The blood flow in areas activated by simple imagining but not by auditory hallucination
• (E) The tendency of the hallucinating brain to behave much like the brain at rest and unexposed to auditory stimulus