Which of the following is the national level system that provides annual national as well as state level reliable estimates of fertility and mortality?

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 fertility and mortality • SRS is a dual record system: Field Investigation: continuous enumeration of births and deaths by an enumerator. Independent retrospective survey: every 6 months by an investigator-supervisor.