Which of the Following Does NOT Describe an Advantage of Experiments

Which of the following does NOT describe an advantage of experiments?

A) With experiments, it is easier to determine whether people's choices are consistent with standard economic theory.
B) With experiments, it is often easier to establish causality.
C) With experiments, researchers can double check their assumptions and conclusions by testing and debriefing subjects.
D) It is generally cheaper to conduct experiments than it is to compute mathematical models.