Which one of the following pairs (sanctuaries and districts) is not properly matched?

The correct answer is C. Gomerda – Raigarh.

Pamer Sanctuary is located in Dantewada district of Chhattisgarh. Badalkhol Sanctuary is located in Jashpur district of Chhattisgarh. Udanti Sanctuary is located in Sarguja district of Chhattisgarh. Gomerda Sanctuary is located in Raigarh district of Chhattisgarh.

However, Gomerda Sanctuary is not a tiger reserve. It is a wildlife sanctuary. A tiger reserve is a protected area that is designated for the conservation of tigers and other wildlife. A wildlife sanctuary is a protected area that is designated for the conservation of wildlife, but it does not have the same level of protection as a tiger reserve.