The Economic Research on Human Happiness, Human Psychology, and Neuroscience

The economic research on human happiness, human psychology, and neuroscience suggests that, among other things:

A) social welfare function can indeed be represented as a simple aggregation of individual welfare functions.
B) change in the distribution of income must result in a new social welfare function and, therefore, a different set of social indifference curves.
C) human ready acceptance of economic changes means economists need not take adjustment costs into consideration in calculating the gains from trade.
D) All of the above.
E) None of the above.