Passage Summary: Even though patients ask for them, doctors shouldn't give out antibiotics for colds because they don't work on viruses and can actually be dangerous.

Conclusion: Physicians ought to refrain from prescribing antibiotics as a treatment for the common cold.

Reasoning: Antibiotics are ineffective against the viral causes of colds and carry risks of harmful side effects.

Analysis: The argument moves from facts about ineffectiveness and risk to a moral or professional 'should.' To bridge this gap, we need a principle that connects the lack of benefit and the presence of risk to a prohibition on the action. Look for an answer that establishes a rule such as: if a treatment provides no benefit but carries risk, it should not be administered.