This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Toxicology, Subject name: Medicine
Acute onset areflexic quadriparesis with blurred vision and absent pupillary response in a 20 years old male, the most probable diagnosis is? 
Select and explain. 
A. Porphyria, B. Botulism, C. Polio, D. Diphtheria
B: Botulism
Answer: B: Botulism 
Explanation: ANSWER: (B) BotulismREF: Harrison s 17th ed p. 901, CMDT - 2006/1410The clinical picture is most consistent with diagnosis of botulismBotulismh/o recent injection of canned or smoked foods or injection of drugSymmetric descending paralysis with prominent bulbar palsyDiplopia , dysarthria , dysphonia , dysphagiaPupils are fixed and dilatedPtosis and cranial nerve palsy with impairment of extra ocular muscles and fixed dilated pupils are characteristic signsSensory examination is normalNormal sensoriumAfebrile