The correct answer is A) Khammam.
Khammam district is one of the most mineral-rich districts in Telangana. It is home to several gold mines, including the Peddapalli gold mine, which is one of the largest gold mines in India. The district also has reserves of other minerals, such as copper, iron ore, and limestone.
Karimnagar district is also a mineral-rich district, but it is not as well-known for its gold mines as Khammam district. The district has reserves of other minerals, such as coal, iron ore, and limestone.
Nalgonda district is not as mineral-rich as Khammam and Karimnagar districts. However, the district does have some reserves of gold and other minerals.
Mahabubnagar district is the least mineral-rich district of Telangana. The district does not have any known gold mines.
In conclusion, the district with potential for gold mining in Telangana is Khammam.