答案：A

解析：

If 6 apples weigh 1 pound, then a dozen (12) apples weigh 2 pounds. The price of a dozen apples is the price of 2 pounds of apples. The price of 10 pounds of apples is d dollars, or 100d cents, so the price of 2 pounds of apples is 1 over 5 of 100d cents, or 20d cents.