Statistical data provided by the u. s. department of transportation shows that the median income of individuals traveling on the nation's bus systems is $18,000 compared to $65,000 for those who normally travel by air. this finding is best explained by which of the following statements?
a. persons with high income are more likely to fly because the opportunity cost of their time is generally higher than those with lesser income.
b. traditionally, lower income groups prefer slower methods of transportation.
c. wealthy individuals own stock in the airlines and, therefore, receive preferential treatment.
d. low-income groups are generally located near bus stations; wealthy groups congregate around airports