So quickly are science and technology advancing is a possibility today may be a reality tomorrow.
A. which
B. what
C. that which
D. that what
网友回答
A. which
B. what
C. that which
(答案→)D. that what
解析：D 考察典型句式和名词性从句。So…that引导的是结果状语从句，so位于句首引起部分倒装，在结果状语从句中有一个由what引导的主语从句。