Their economies rely heavily on exports.
Answer: Option C
Step-by-step explanation:
OPEC is an organisation for countries that export petroleum. This organisation serves as a link between the oil producing countries. It fixes the price does the marketing provides a platform for the countries to sell their petroleum products.
There are 14 major oil producing countries which are into this organisation out of which the major oil producing countries like Russia, China and United States are not a part of it. Their countries economy is mainly dependent upon the exports. They are the ones deciding the market price where they always have it in a hike and enjoy shares in the global market.