As a result of is now known in physics and chemistry, scientists have been able to make important discoveries in biology and medicine.
A. it
B. what
C. which
D. that
网友回答
A. it
(答案→)B. what
C. which
D. that
解析：句意：由于在物理学和化学上已知的知识的原因，科学家们已经能够在生物学和医药上取得重要发现。what 引导宾语从句，在从句中做主语。在宾语从句中，which 是哪一个，that不做成分。故选B。
考点: 考查从句关系词的用法。