This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Demography and family planning, Subject name: Social & Preventive Medicine
[{'content': 'Which of the following is the national system that provides annual national as well as state reliable estimates of feility and Moality \nSelect and explain. \nA. Civil registration system, B. Census, C. Ad-hoc survey, D. Sample registration system', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Sample registration system (SRS) : Was initiated in 1964-65 (on a pilot basis ; Full scale from 1969-70) to provide national as well as state level reliable estimates of feility and Moality SRS is a dual record system Field investigation : Continuous enumeration of bihs and deaths by an enumerator Independent retrospective survey : Every 6 months by an investigator-supervisor Findings of SRS survey Crude bih rate (CBR) : 20.4 per 1000 mid year population Crude Death rate (CDR) : 6. 4 per 1000 mid year population Natural growth rate : 14% Infant Moality rate (IMR) : 34 per 1000 live bihs Ref: Park 23rd edition 904', 'role': 'assistant'}]