It is said that the rational consumer will act according to his or her self-interest, and that self-interest can include a concern for one's family and friends, but not often society as a whole. Which of the following illustrates this type of decision?

Select one:

a. The rental of recreational vehicles for use in national parks is responsive to concerns of noise pollution.

b. Our time was very valuable at that moment, but we stopped to put out the fire before it spread.

c. Mr. T. decides not to purchase any case of water bottle so there could be more left for other consumers.

d. The boat rental was worth the additional fish caught, regardless of how little fish we left behind.