The correct answer is (c). The sex ratio (females per 1000 males) in Bihar has shown a decline over the past few decades. In 1991, the sex ratio was 917 females per 1000 males. This declined to 909 in 2001, 891 in 2011, and 893 in 2021. This decline is likely due to a number of factors, including female infanticide, sex-selective abortion, and neglect of girls.
Option (a) is incorrect because the sex ratio in Bihar has not shown a steady improvement. In fact, it has shown a decline over the past few decades.
Option (b) is incorrect because the sex ratio in Bihar has shown a decline over the past few decades.
Option (d) is incorrect because the sex ratio in Bihar has not shown large fluctuations. It has shown a steady decline over the past few decades.