Question #N441

The following passage is from a science article: "Many people have heard of the placebo effect: the phenomenon in which people feel better even if they are given a fake treatment. But the placebo effect is not just about relieving symptoms; it can also affect other measurable outcomes, such as the body's stress response. For instance, one study found that even the expectation of receiving a placebo resulted in a decrease in the production of the stress hormone cortisol. This effect may be related to the fact that the brain has a powerful influence on how the body functions, but more research is needed to fully understand how placebos work."

In the passage, the author uses the example of the study about the placebo effect to
A. provide evidence that the placebo effect can affect more than just symptoms.
B. explain why the placebo effect is related to the body's stress response.
C. suggest that the brain has a powerful influence on how the body functions.
D. conclude that more research is needed to understand how placebos work.