This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Measurement of Mortality and Morbidity, Subject name: Social & Preventive Medicine
[{'content': 'Out of 10 relatives exposed to a primary case, of measles, 6 developed measles. Secondary attack rate of measles- \nSelect and explain. \nA. 10-Apr, B. 10-Jun, C. 6-Apr, D. 4-Jun', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. is \'b\' i.e., 6/10 Secondary attack rate (SAR)o SAR is defined as "the number ofexposed persons developing the disease within the range of incubation period, following exposure to primary caseSAR=No of exposed persons developing disease withinthe range of the incubation period-----------------------Total number of exposed/susceptible contactx 100 SAR =610x 100', 'role': 'assistant'}]