单选题 The waterfall_______the rocks.
A. wears down
B. wears off
C. wears away
D. wears out

【正确答案】 C

【答案解析】[解析] weardown意为“(使某物)逐渐变小、变细、变薄等”；wearoff意为“(使某物)逐渐消失或除去”；wearaway意为“(使某物)用薄、用细、用坏或用旧等”；wearout意为“(使某物)用得不能再用、用坏、耗尽”。根据句意可知。故本题答案为C。