【单选题】

Which of the following best expresses the main idea of the passage
A．(A) Research has suggested that positron emission tomography will soon answer most skeptical objections the existence of the phenomenon of hypnosis.

B．(B) Researchers have spent an adequate amount of time allaying skepticism concerning the effects of hypnosis, though more needs to be understood.
C．(C) Research results strongly suggest that hypnosis techniques, especially those that create pain relief, may have a medicinal value in the future.
D．(D) Researchers have recently made valuable discoveries concerning the potential of hypnosis in creating auditory hallucinations.
E．(E) Researchers have failed to present incontrovertible evidence that skeptical explanations of the hypnosis phenomenon are unwarranted.