An analysis of a large-scale survey of consumer food purchases by mark aguiar and erik hurst indicates that retired people spend less for the same market basket of food than working people do. use the concept of opportunity costto explain this fact. a)the opportunity cost of time for retired people is lower than the opportunity cost of time for working people, so retirees spend more time pursuing their favorite leisure activities and less time shopping for necessities. b)the opportunity cost of time for retired people is lower than the opportunity cost of time for working people, so retirees choose to spend more time shopping for lower-priced items compared to people who are still working. c)the opportunity cost of time for retired people is identical to the opportunity cost of time for working people, because each minute is equally valuable regardless of one's employment status. d)the opportunity cost of time for retired people is higher than the opportunity cost of time for working people, so retirees choose to search longer for bargains for the items they buy.