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: Forensic Medicine
[{'content': "A middle aged man presents with parasthesia of hands and feet. Examination reveals presence of `Mees' lines in the nails and rain drop pigmentation in the hands. The most likely causative toxin for the above mentioned symptoms is - \nSelect and explain. \nA. Lead, B. Arsenic, C. Thallium, D. Mercury", 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]