Psychologist: Some theories posit completely different causal mechanisms from those posited by the Smith psychological theory that are more successful at predicting human behavior. Therefore, the Smith theory of behavior, no matter how elegant or complex, ought to be abandoned in favor of these other theories.

Which of the following is an assumption made in drawing the conclusion above?

A) The Smith theory has led to intriguing predictions,which have been shown to be false, about the causes of human behavior.
B)A psychological theory with greater predictive success than another is scientifically preferable.
C) The Smith theory has had remarkable success in predicting how people will behave in certain situations.
D) Measuring the predictive success of a psychological theory always involves considering other theories that attempt to explain the same phenomena.
E) Scientific theories become impractical if they posit causal mechanisms beyond a certain level of complexity.