The Focus on Neuroscience Box, "The Mysterious Placebo Effect," Described

The Focus on Neuroscience box, "The Mysterious Placebo Effect," described a PET-scan study on the placebo effect. Which of the following was found in the study?

A) The opiate painkiller activated a brain area known to contain many opioid receptors, but the placebo activated areas of the brain with no opioid receptors.
B) Both the placebo and the opiate painkiller activated a brain area known to contain many opioid receptors.
C) The opiate painkiller activated a brain area known to contain many opioid receptors, but the placebo inhibited activation in the same area.
D) The placebo activated a brain area known to contain many opioid receptors, but the opiate painkiller activated areas of the brain with no opioid receptors.