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: Microbiology
[{'content': 'All of the following statements about E1-Tor vibrios are true, Except - \nSelect and explain. \nA. Humans are the only reservoir, B. Can survive in ice cold water for 2-4 weeks, C. Killed by boiling for 30 seconds, D. Enterotoxin can have direct effects on other tissues besides intestinal epithelial cells', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]