The correct answer is: c) Mica.
Mica is a mineral that is used in a variety of products, including electronics, cosmetics, and roofing materials. It is found in abundance in Meghalaya, and small-scale mining of mica is a major economic activity in some parts of the state.
Copper is a metal that is used in a variety of products, including electrical wiring, plumbing fixtures, and coins. It is not found in abundance in Meghalaya, and small-scale mining of copper is not a major economic activity in the state.
Gold is a precious metal that is used in jewelry and other decorative items. It is found in small quantities in Meghalaya, but small-scale mining of gold is not a major economic activity in the state.
Uranium is a radioactive metal that is used in nuclear power plants. It is not found in abundance in Meghalaya, and small-scale mining of uranium is not a major economic activity in the state.