一道关于in which的大全题

Until quite recently, American presidents lived in a world in which the public and private realms of their lives were largely separate, and the press cooperated in maintaining the distinction, and Americans judged national leader without receiving, or expecting, intimate information about them.

(a)and the press coorperated in maintaining the distinction ,and

(b)where the press cooperated in maintaining the distinction, and where

(c)for the press cooperated to maintain the distinction and

(d)the press cooperated to maintain the distinction, for

(e)in which the press cooperated in maintaining the distinction, and in which

答案选E

  我觉得不对，如果选E的话, 那么which 完全可以说指代不明呀，在前面的句子里应该可以很多被which指代。

  我觉得应该选C，for 后面连接的两个句子是对American presidents lived in a world in whichi the public and private realms of their lives were laregely separate的解释，一个是因为媒体很配合，保持了总统们这样的生活工作界限，另一个原因美国民众的观点也导致了美国总统一个这样的生活黄台，for在这里引导原因状语从句。

我不知道我这样解释是不是对，请牛牛们指教~~

应该E里面的in which 是和前面未划线部分的in a world in which the public and private...里面的in which是对称的。加上后面的and in which刚好是三个in which 并列。所以which都是指代world 的。