This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Infection, Subject name: Medicine
[{'content': 'An 18-year-old male presented with acute onset descending paralysis of 3 days duration. There is also a history of blurring of vision for the same duration. On examination, the patient has quadriparesis with areflexia. Both the pupils are non-reactive. The most probable diagnosis is - \nSelect and explain. \nA. Poliomyelitis, B. Botulism, C. Diptheria, D. Porphyria', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Botulism is caused by neurotoxins of Clostridium botulinum, which are extremely potent & cause disease after ingestion of even picogram amounts. Its classical form is an acute onset of bilateral cranial neuropathies associated with symmetric descending weakness.The toxin causes predominantly bulbar & ocular palsies(difficulty in swallowing ,blurred or double vision ,ptosis),progressive to limb weakness & respiratory paralysis . Reference Harrison20th edition pg 1027', 'role': 'assistant'}]