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': 'In blood culture the ratio of blood to reagent is \nSelect and explain. \nA. 1:05, B. 1:20, C. 1:10, D. 0.111111111', 'role': 'user'}, {'content': "Answer: C \nExplanation: Ans. is 'c' i.e., 1:10 Blood specimens of 5 or 10 ml generally are added to bottles containing, 50 or 100 ml of reagent (medium) to achieve a 1:10 blood medium ratio. All bottles should be transpoed to the laboratory as soon as possible and immediately incubeted at 35 +- 2degC in an upright position (Note - Lower incubation temperature may be preferred for isolation of some specific bacteria, e.g. Listeria grows well at 20-25degC). A total incubation period of 7 days is generally sufficient for routine isolation procedure, which can be extended up to 14 days before discarding those that do not show evidence of growth.", 'role': 'assistant'}]