The correct answer is "2 only," as the primary purpose of District Mineral Foundations (DMFs) in India is to protect the interests of communities adversely affected by mining operations. DMFs are established under the Mines and Minerals (Development and Regulation) Act, 1957, to ensure that a portion of the mineral royalties is used for the welfare of local communities, including providing for their health, education, and infrastructure needs, thereby addressing the socio-economic impact of mining activities. The other options relate to functions not assigned to DMFs, as they do not promote mineral exploration or authorize licenses, which fall under the purview of state mining policies.