This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nutrition and Metabolic disorders,Systemic conditions ,Genodermatoses, Connective tissue disorders,Photodermatoses, Subject name: Dental
[{'content': "Vibration white finger: \nSelect and explain. \nA. Consist of Raynaud's phenomenon and loss of sensation, B. Main pathogenic mechanism is severe degeneration of nerves, C. Computer geeks are at risk of developing it, D. Ice provocation test is always reliable in precipitating attacks", 'role': 'user'}, {'content': "Answer: A \nExplanation: Vibration white finger (VWF) Episodic appearance of white-finger skin patches (Raynaud's phenomenon) in response to environmental cold. Is accompanied by secondary loss of sensation caused by vascular ischaemia. It can be pa of, but is not synonymous with Hand-arm vibration syndrome.", 'role': 'assistant'}]