Which of the following is a normative economic statement?
a. with rising mortgage rates and rising unemployment rates, the number of unsold homes has increased.
b. rising global demand for coal has led to increases in the price of coal.
c. the state of texas is considering increasing funds for light-rail development to promote the use of public transportation.
d. pharmaceutical manufacturers should not be allowed to patent their products so prescription drugs would be more affordable.

Robert black, regional manager for ford in texas and oklahoma, faced a dilemma. the ford f-150 pickup truck was the best-selling pickup ever, yet ford's headquarters in detroit had decided to introduce a completely redesigned f-150. how could mr. black sell both trucks at the same time? he still had "old" f-150s in stock. in his advertising, mr. black referred to the new f-150s as follows: "not a better f-150. just the only truck good enough to be the next f-150." this statement represents ford's of the new f-150.