Behavioral Economists Have Not Discovered Which of the Following Things

Behavioral economists have not discovered which of the following things about people's reaction to losses?

A) People judge losses in relative terms; i.e., relative to the status quo.
B) People experience increasing marginal disutility from losses.
C) People would feel the loss of $1,000 more intensely than they would feel the gain of $1,000.
D) When people lose successive equal amounts, the initial losses are more painful than later ones.