一个很难解释的英语单选题-----------高手帮忙

问题描述:

一个很难解释的英语单选题-----------高手帮忙
upon a true story,the film was very successful in our country.
A:Based B:To base C:Basing D:Being based
从句的省略.从句的主语是the film与base之间存在被动关系.
还原原句:Because it was based upon a true story.the film was very successful in our country.
译:以真实故事为基础,这个电影在我国取得很大成功.
我怎么看不出被动还是主动呢?如果直译的话,应该是“因为电影是被以真实的故事为基础”,真别扭,
如果不纠结主动还是被动,

sth1 base on sth2 “事情1以事情2为基础”换成被动就是:
sth2 be based on sth1 事情2基于事情1
所以呢,你再翻译翻译,这部电影是以一个真实的故事为基础.你最好举个实例。汉语就行。基于我收到的这些题材,我编写了一个感人的故事。跟你说的例题类似的。。。