Mrs. Green went back home hurriedly, where her two little twins were crying, _____     they were hungry.

A．said

B．saying

C．to say

D．having said

一年前，某商品价值为30单位白银，若今年生产该商品的社会劳动生产率提高50%，且白银升值了10%，在其他条件不变的情况下，今年购买该商品需支付的白银约是[ ]

A．18单位

B．18．5单位

C．18．18单位

D．22单位