<s>[INST] context: This is a typical presentation of botulism, which is caused by the preformed toxin of Clostridium botulinum. Patients develop a progressive flaccid paralysis that can lead to death if their respiratory system is not adequately suppoed. Mentation is intact in these patients, and they do not exhibit sensory changes except for those, such as the double vision, related to failure of extra- and intraocular muscles. Note: You are probably aware that botulism can follow ingestion of home canned vegetables, fish, fruits, and condiments. You may not be aware that other vehicles that have been the source of outbreaks include commercially prepared canned foods, poultry, and dairy products; and even restaurant-prepared non-canned foods including seafood, foil-wrapped baked potatoes, chopped garlic in oil, and patty melt sandwiches. For this reason, the absence of a classic history of ingestion of home canned food should not be used to exclude the diagnosis of botulism. Treatment is suppoive. Most patients recover from foodborne botulism without sequelae. You should also be aware that C. botulinum can cause true infection coupled with toxin production in wounds and in infants. Clostridium perfringens is one of the causes of gas gangrene. Clostridium ramosum has been associated with intra-abdominal infections after bowel perforation. Clostridium septicum has complicated colorectal malignancy. [/INST] question: A 34-year-old woman is seen in the emergency depament. About 5 hours previously, she began to have nausea, vomiting, abdominal cramps, and diarrhea. She then developed double vision, which prompted her to ask her husband to bring her to the emergency depament. When she is asked to go into the examining room, she stumbles. When she tries to answer questions, her voice sounds odd and she seems to mumble. Physical examination demonstrates a dry mouth, drooping eyelids, markedly diminished pupillary light reflex, a flaccid facial expression, and difficulty in opening her mouth. Within an hour, her condition has markedly deteriorated. She can no longer stand and is intubated because of difficulty breathing. Which of the following microbial species is MOST likely to have caused her condition? | options: A: Clostridium botulinum B: Clostridium perfringens C: Clostridium ramosum D: Clostridium septicum | answer: A </s>