This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Intestinal Infections, Worm Infestations, Subject name: Social & Preventive Medicine
[{'content': 'Which of the following disease has incubation period< 1week? \nSelect and explain. \nA. Cholera, B. Kala-azar, C. Filariasis, D. Measles', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Incubation period of cholera: 1-2 days. Incubation period of kala azar: 1-4 months. Incubation period of filariasis: 8-16 months. Incubation period of measles: 10-14 days.', 'role': 'assistant'}]