Business Opportunities in the Clean-Tech Economy Have Much Potential

Business opportunities in the clean-tech economy have much potential.Production of solar panels in China has brought the prices down by 50%,while many countries are providing incentives to invest in the field.However,in strategy we must always look at both opportunities and threats.Which of the following is NOT a threat to the growth of the clean-tech economy?

A) The energy sector is rapidly growing worldwide.
B) It is not currently cost-competitive with coal and oil.
C) The U.S. has 30% of the world's known coal reserves.
D) Market externalities are not priced into current fossil fuels.