We are looking for the answer choice which outlines a principle that helps to strengthen the physician's argument.
The physician concludes that clinical psychologists who are not also doctors should not be allowed to prescribe psychiatric medications.
Why? Training to become a clinical psychologist only requires at most a few hundred hours of education whereas training to become a doctor requires years of education before they are allowed to prescribe psychiatric medications.
Answer choice (C) is correct because it strengthens the physician's ability to draw their conclusion. What is the difference between clinical psychologists and doctors? The amount of education they are required to receive.
If we accept that no one without years of training in neuroscience, physiology, and pharmacology should be allowed to prescribe psychiatric medications, then it logically follows that clinical psychologists should not be allowed to prescribe these medications as they only have a few hundred hours of training in these fields.
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