Explanation:

Here’s the thing: the Economic Survey 2018-19 actually made a point about the total fertility rate (TFR)—that’s the average number of children a woman will have in her lifetime—falling below the replacement rate, which is 2.1. That’s the threshold needed to keep population levels stable.

- The Survey predicted that India’s national TFR would drop below this replacement rate by 2021.

- Here’s why this matters: falling below 2.1 means, over time, population growth will slow and could eventually decline. That brings up a whole set of challenges for workforce, aging, and economy.

- Let’s nail down the options:

- 2024 (too late, trend was faster)

- 2025 (even later, not what the data suggested)

- 2022 (close, but still not the year mentioned)

- 2021 ( Exactly what the Survey said)

- Many states already dipped below replacement levels before, but this was about national average.