Which of the Following Is a Reason for Using Our

Which of the following is a reason for using our unconventional reserves if they were more difficult to obtain?

A) Conventional reserves must be transported long distances,and are subject to spills and environmental disasters.
B) It is too expensive to import oil from other countries where the conventional reserves are located.
C) Unconventional reserves can help us become energy independent and rely less on energy imports.
D) The technology of using renewable energy sources is unreliable and too expensive to produce energy on a scale for our needs.