Coal is a very useful rock that formed over millions of years from the remains of plants. Is coal a mineral?
A. No, coal is not a mineral because coal can be burned to produce electricity and heat.
B. Yes, coal is a mineral because all rocks are nonliving solid minerals.
C. Yes, coal is a mineral because all rocks that are useful to people are minerals.
D. No, coal is not a mineral because coal is made of dead plants.