Paragraph 4 supports which of the following statements about future petroleum discoveries? A. Less petroleum will be found than in the past because the ratio of petroleum pools to volume of sediment will decrease. B. Most of the petroleum will come from rocks that are less than 65 million years old. C. Petroleum that has leaked away from older rocks will be the source of most new discoveries. D. More petroleum will become available because the amount of trapped organic matter will increase.