This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Communicable diseases, Subject name: Social & Preventive Medicine
[{'content': 'Infective period of chicken pox is \nSelect and explain. \nA. 2 days before and 2 days after rash appearance, B. 2 days before and 5 days after rash appearance, C. 4 days before and 4 days after rash appearance, D. 4 days before and 5 days after rash appearance', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Chicken Pox Synonym: Varicella Causative agent : Varicella zoster virus Incubation period: 14-16 days Source of infection : Case (person-to-person contact) Mode of transmission : Air droplets (respiratory) Period of communicability : 1-2 days before to 4-5 days after appearance of rash Secondary Attack rate : 90% Rash: Dew drop on rose petal Apperance. Centripetal distribution pleomorphic rash Ref: Park 25th edition Pgno : 157', 'role': 'assistant'}]