b then it implies that (1) sometimes the vantage point was combined with the writing and sometimes it wasn't, and (2) it only made her valuable when it was combined with the writing talent. that doesn't make sense.事实上没有一种情况是这个vantage point 是不在这个时间的，所以说用when 去形容，之所以是vantage point 就是以你为这几个因素的结合。而不是说本来就有一个vantage point只有在这个时期有了talents 才能让她有价值。

b then it implies that (1) sometimes the vantage point was combined with the writing and sometimes it wasn't, and (2) it only made her valuable when it was combined with the writing talent. that doesn't make sense.事实上没有一种情况是这个vantage point 是不在这个时间的，所以说用when 去形容，之所以是vantage point 就是以你为这几个因素的结合。而不是说本来就有一个vantage point只有在这个时期有了talents 才能让她有价值。

原句句子结构：Because she knew..., Mercy Otis Warren was c..., a vantage point combining ...
原句逻辑语义：因为他知道许多美国殖民地的领导和美国革命，Mercy Otis Warren从1765-1789一直在政治的重心或者周边，一个有利的点结合了她写作的才能让她成为那个时代最有价值的历史学家之一。
A.combining错误，应该为combined；
B.when combined应该修饰made，应放在that之后；
C.and it和前面不平行；
D.and后无谓语；
E.正确

It sounds to me that a vantage point performs the action that combines with her talent, and also, make should be made.

做题需认真、仔细、严谨。此题绝不应该做错。

A. to make表将来含义，而句子描述的是过去已经确定的事实，时态含义不符;combining应该为combined

this vantage point指代是前面的句子 前面指出的有利条件与她在写作上的天赋结合使得她成为·····B选项无故添加了时间状语从句，该改变了句意

a vantage point前面没有任何一个词是point，所以不能做同位语

关于this:
it's incorrect to use "this" as a STANDALONE PRONOUN. i.e., you cannot write something like "this, combined with her talent for writing, made her..."

however, "this" as an ADJECTIVE (the way in which it is used here, in front of the noun "vantage point") is just fine, and is quite exceedingly common.

B：actually, in choice b, 'when' doesn't refer to anything - there's no time period to which it could logically refer - and that's the main issue with choice b. (if you interpret it literally, as you must, then it implies that (1) sometimes the vantage point was combined with the writing and sometimes it wasn't, and (2) it only made her valuable when it was combined with the writing talent. that doesn't make sense.)

这里为什么要用个and?