单选题 A scientific law is liable at any time to need modifying. This happens when fact is discovered which seems to ______ what the law would lead one to expect.

【正确答案】 C
【答案解析】“一项科学定律随时都可能需要改进”是“(当新的事实)违背(该定律时)”时，因此选contradict“与……相矛盾”。prove证实；support支持；discourage (something)使(某事)难以发生。