The healing power of positive expectations is best illustrated by

A. overconfidence.

B. illusory correlation.

C. the placebo effect.

D. hindsight bias.

The correct answer is C) The Placebo Effect

Explanation:

In medical terms, a placebo effect occurs when a patient is given an inactive medicine that does not work but the patient has no prior knowledge of this. However, due to their own expectations, slight improvements in their conditions are noted which are mostly attributed to the patient's own positive belief in the medicine.

The Placebo effect is well-documented. Positive exceptions has such a powerful impact on the outcome that scientific research, always includes a separate section to measure the effect of a medicine compared to a placebo group.