Answer : 3. "Arunachal Pradesh"
Explanation :

Indian researchers have recently discovered a unique type of blue ant species in Siang Valley, a "biodiversity hotspot" in Arunachal Pradesh. Researchers from the Ashoka Trust for Research in Ecology and the Environment (ATREE) have discovered it. According to ATREE researchers, the species has been named Paraparatrechina neela, which is "different from common red, black or brown ants.