Which of the following is an example of positive feedback?
a. breathing and heart rate increase as a person climbs a set of stairs
b. sweating when hot so that as sweat evaporates the body is cooled
c. the increase in milk production while a mother is nursing her infant
d. constriction of the pupils when the eyes are exposed to bright light

A. breathing and heart rate increase as a person climbs a set of stairs

Explanation:

"choosing is refusing" means individuals face an opportunity cost with each decision they make. economists state that every decision involves trade-offs. opportunity cost is the least desirable alternative given up as a result of a decision.

answer; one person; monarch;