Correct Answer: 1911-21

Solution : The correct option is 1911-21.

India witnessed a unique phenomenon of negative population growth rate from 1911 to 1921, which was mostly related to the catastrophic impact of the 1918 influenza pandemic, often known as the Spanish flu. This lethal epidemic has far-reaching implications for communities all throughout the world, including India. The H1N1 influenza virus produced the Spanish flu, which is regarded as one of the worst pandemics in human history. It is believed that it infected around one-third of the world's population and caused a substantial number of fatalities.