Oil, natural gas, and coal are considered to be nonrenewable resources. why are these fuels considered to be nonrenewable? a) the burning of these fuels does not allow the waste products to be recycled. b) these fuels are available in a limited supply--when the fuel is used it is no longer available. c) the amount of pollution released from the use of these fuels is much higher than with renewable sources. d) the technology used to generate energy by the use of these fuels is much older and less efficient than current technology.