The author’s argument closely conforms to this principle because he argues that doctors shouldn’t prescribe antibiotics for colds since they cannot improve colds and since they potentially have adverse side effects.

The author’s argument doesn’t conform to this principle because he’s only addressing a drug that does not have a positive effect on certain patients. He might think that some potentially harmful drugs are worth the risk if they’re effective.

The author’s argument doesn’t conform to this principle because he’s arguing that antibiotics should not be prescribed for colds. Also, he’s addressing a drug that will not affect cold patients’ health positively.

The author establishes that antibiotics will not benefit patients with colds, so antibiotics aren’t even a treatment for colds. Instead of (D), we need to establish that doctors should withhold a drug from patients if that drug is ineffective and potentially harmful.

The author’s argument doesn’t conform to this principle. He says doctors shouldn’t prescribe antibiotics for colds because they don’t work and might be harmful—not because patients believe they work.