The correct answer is A. Reasi.
According to the 2011 census, the child population (0-6 years) in Reasi district was 12.4%, which is the lowest among all the districts of Jammu and Kashmir. The child population in Samba district was 13.2%, Shopian district was 13.5%, and Kishtwar district was 14.1%.
There are a number of factors that could contribute to the low child population in Reasi district. One possibility is that the district has a higher proportion of elderly people than other districts. Another possibility is that the district has a lower fertility rate than other districts. Finally, it is also possible that the district has a higher rate of child mortality than other districts.
Whatever the reasons, the low child population in Reasi district is a cause for concern. A low child population can lead to a number of problems, including a shrinking workforce, a smaller tax base, and an aging population. It is important to understand the reasons for the low child population in Reasi district and to take steps to address the issue.