would,can, may都有“可能”的意思

我的问题是，这几个词在说一件事情可能发生的时候，肯定的程度哪个最大，哪个最小呢?谢谢！

问题起因

OG 171

In 1527 King Henry VIII sought to have his marriage to Queen Catherine annulled so as to marry Anne Boleyn. (A) so as to marry (B) and so could be married to (C) to be married to (D) so that he could marry (E) in order that he would marry

The explanation of OG about answer E is that the verb form would marry is unidiomatic and illogical ( might marry would be better ).