Which of the following topics are more likely to be studied by a macroeconomist than by a microeconomist?
A、the effect of taxes on the prices of airline tickets, the profitability of automobile-manufacturing firms, and employment trends in the food-service industry
B、the price of beef, wage differences between genders, and antitrust laws
C、how consumers maximize utility, and how prices are established in markets for agricultural products
D、the percentage of the labor force that is out of work, and differences in average income from country to country