This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Surgery
[{'content': 'Most common presenting symptom of acute arterial occlusion: \nSelect and explain. \nA. Pain, B. Pallor, C. Pulselessness, D. Paralysis', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Peripheral Arterial Occlusion\n\nClinical features of peripheral arterial occlusion are classically remembered by 5 Ps: Pain, Pallor, Pulselessness, Paralysis and Paraesthesia (or anesthesia)\nSome add 6th P: Poikilothermia or perishing cold\nMC presenting symptom of acute arterial occlusion: Pain', 'role': 'assistant'}]