This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Epidemiology, Subject name: Social & Preventive Medicine
[{'content': 'All of the following are used as proxy measure for incubation period except- \nSelect and explain. \nA. Latent period, B. Period of communicablity, C. Serial interval, D. Generation time', 'role': 'user'}, {'content': "Answer: B \nExplanation: Incubation period is the time interval between invasion by an infectious agent and appearance of 1st sign or symptom of disease whereas the period of communicability is the time during which an infectious agent may be transferred directly or indirectly from an infected person to another. Ref: 25th edition, Park's Textbook of Preventive and Social Medicine, Page no. 107, 108", 'role': 'assistant'}]