Which of the following sets of events must cause an increase in the price of a new house?
a. higher wages for carpenters, higher wood prices, increases in consumer incomes, higher apartment rents, increases in population, and expectations of higher house prices in the future
b. lower wages for carpenters, lower wood prices, increases in consumer incomes, higher apartment rents, increases in population and expectations of higher house prices in the future
c. lower wages for carpenters, higher wood prices, decreases in consumer incomes, higher apartment rents, decreases in populations and expectations of higher house prices in the future
d. higher wages for carpenters, lower wood prices, decreases in consumer incomes, lower apartment rents, decreases in population and expectations of lower house prices in the future