Sometimes economists disagree because their values differ. which of the following instances best reflects this source of disagreement?
a. one economist believes that, prior to the civil war, slavery contributed to economic growth in the south; another economist believes that slavery held back the south's economic growth.
b. one economist believes the north american free trade agreement (nafta) has led to a loss of american jobs; another economist disputes this claim.
c. one economist advises against increases in sales taxes because she thinks such increases are unfair to low-income people; another economist disputes the idea that increases in sales taxes are unfair to low-income people. d. one economist believes that, when income taxes are cut, people will increase their spending; another economist believes that, when income taxes are cut, people will increase their saving.