TOEFL Reading: ETS-TOEFL阅读机经 - 0RO81718AM2OS63OL$

According to paragraph 2, which of the following is true about parent material found at a given site? A. It was most likely deposited there by glaciers rather than by wind and water. B. It is formed and consolidated entirely from the bedrock on which it rests. C. It can vary in its richness and fertility according to where it originated. D. The speed with which it is transported determines its location.