All of the following, if true, explain why treatment in an emergency room costs more than treatment in a physician's private office EXCEPT: A. The medical equipment in hospital emergency rooms is more sophisticated and elaborated than that found in physicians' private offices. B. When patients come to physicians' private offices, the state of their illness is usually such that physicians have time to try one test or medication at a time in order to monitor the results. C. The variety of illnesses treated by emergency room physicians is much smaller than the variety treated by physicians in their offices. D. The illness of many patients who apply for emergency room treatment is so severe that physicians apply several remedies at once in the hope of obtaining immediate results. E. In emergency rooms a patient is often attended by nurses, paramedics, and physicians, whereas visits of private office rarely involve more than two staff members.