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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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Postganglionic sympathetic fibres are
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The correct answer is  The axons of postganglionic neurons are mostly unmyelinated C fibres and terminate on visceral effectors. Ref: Ganong&;s review of medical physiology; 23rd edition; pg:263.