GMAT Critical Reasoning (CR) | Some public health advocates have become concerned that

If Physicians ARE susceptible to pressure from patients in determining appropriate courses of treatment then advertising the medication is in accordance to what the public health advocates say. So we need to negate this possibility by saying "physicians ARE NOT" susceptible to pressure from patients. So D is correct.

C is incorrect because what it says is already stated in argument as "as long as physicians also continue to be educated about such medications".

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