This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nervous system, Subject name: Physiology
Cutaneous vasoconstriction is mediated by 
Select and explain. 
A. Sympathetic adrenergic nerves, B. Sympathetic cholinergic nerves, C. Parasympathetic cholinergics, D. Somatic nerves
A: Sympathetic adrenergic nerves
Answer: A: Sympathetic adrenergic nerves 
Explanation: Sympathetic noradrenergic division constricts the blood vessels of the skin(which limits bleeding from wounds). Ref: Ganong&;s review of medical physiology; 23rd edition; pg: 268.