Billy developed an economic model to describe the behavior of a stock

Billy developed an economic model to describe the behavior of a stock market index. His model predicts that the index increases on Mondays and declines on the other days of the week. What can be said about Billy’s model?

A) The model’s predictions are ambiguous and cannot be tested.
B) The model’s predictions are not ambiguous and cannot be tested.
C) The model’s predictions are ambiguous and can be tested.
D) The model’s predictions are not ambiguous and can be tested.

ANSWER

D