单选题 Output is now six times ______ it was before liberation.
A. that B. which C. what D. as much

【正确答案】 C

【答案解析】[解析] 现在的产量是解放前产量的六倍。what it is/was是个很有用的句式，表示前面所提到的同类情况，如：Life in the nineteenth century was very different from what it is now．又如：The situation is very different from what it was twenty years ago．