The correct answer is (c), Arunachal Pradesh.
Scheduled Castes (SCs) are a group of people in India who have been historically discriminated against and marginalized. They are listed in the Indian Constitution as being socially and educationally backward. The Constitution provides for special provisions for SCs in order to improve their social and economic status.
According to the 2011 census, the population of SCs in India was 16.66% of the total population. The states with the highest proportion of SCs were Punjab (32.09%), Haryana (28.79%), and Uttar Pradesh (21.18%). The states with the lowest proportion of SCs were Sikkim (0.02%), Nagaland (0.03%), and Arunachal Pradesh (0.04%).
The low proportion of SCs in Arunachal Pradesh is likely due to the fact that the state has a very small population and a high proportion of tribal people. Tribal people are not included in the list of SCs.
The other options are incorrect because they all have a significant population of SCs.