Correct Answer: (d) 2001-2011
Solution:The decadal growth rate of the population in the decade 1901 to 1911 was 5.75 percent and in the decade of 1911-1921, the decadal growth rate of the population of India became negative (-0.31%). As a result, the population of India remained more or less stable during the period 1901-21. In the three decades of the period 1921 to 1951, there was a steady increase in population, which was 11%, 14.22% and 13.31% respectively. The period from 1951 to 1981 reflected a very rapid increase in population in India. In these three decades, population growth was recorded as 21.51%, 24.80% and 24.66% respectively. After 1981, there has been increase in India's population, but the growth rate is gradually decreasing during this period. Therefore, this period is characterized by high growth with definite signs of slowdown. The population growth rates in the decades of 1991, 2001 and 2011 have been 23.87%, 21.54% and 17,7% respectively.