在公差为d的等差数列{a_n}中，我们可以得到a_n=a_m+（n﹣m）d （m，n∈N₊）．通过类比推理，在公比为q的等比数列{b_n}中，我们可得（　　）

A．b_n=b_m+q^n﹣m

B．b_n=b_m+q^m﹣n

C．b_n=b_m×q^m﹣n

D．b_n=b_m×q^n﹣m

Not until I began to work ____ how much time I had wasted.

A．didn't I realize

B．did I realize

C．I didn't realize

D．I realized