复习时，无意中又发现0G 4中一个迷惑

4.     The only way for growers to salvage frozen citrus is to process them quickly into juice concentrate before they rot when warmer weather returns.

(A) to process them quickly into juice concentrate before they rot when warmer weather returns

(B) if they are quickly processed into juice concentrate before warmer weather returns to rot them

(C) for them to be processed quickly into juice concentrate before the fruit rots when warmer weather returns

(D) if the fruit is quickly processed into juice concentrate before they rot when warmer weather returns（E）

(E) to have it quickly processed into juice concentrate before warmer weather returns and rots the fruit

即citrus为单数，但复数形式是：citrus / citruses，所以根据OG：Choice A begins with an infinitive, but the plural pronouns them and they do not agree with the singular noun citrus，即死认citrus为单数

搜索了一下，发现早有此疑问，但还是没人能说清，http://forum.chasedream.com/dispbbs.asp?BoardID=23&ID=19269

谢了rhod,

我是在想，如果A也能当复数，A选项就只有　before --when用在一起不好，好象这一个缺陷了，很难排除啊

A选项有点问题,

选项中的”them”指涉不清，还有后面的”they”也是指涉不清，因为若将citrus当成复数，则them及they将可以代替”growers”或是”citrus”，造成句子意思不清，像E选项就非常清楚，it 只能指前面的citrus，而后面rots 以the fruit为受词而不用it是为了避免混淆，因为再用it可能是指”citrus”或是”juice concentrate”，语意又不清，故用the fruit避免混淆

ETS出题真是相当深奥.

问：说代词指代不清是按照它在句中的意思吗？是不是代词指代时也有类似定语从句一样只修饰和它最近的词或句这样的说法，如果这样就不存在指代不清的问题了反正是有规则吗？

请指教我希望我的汉语说明白了我要表达的。

谢谢！