Prep-T2-Q105

Test2-105. (29961-!-item-!-188;#058&004575)

2001 proved to be the automaker's first losing year since 1992, when the company had lost $7.4 billion, which was primarily because of almost $7 billion in accounting charges.

(A) when the company had lost $7.4 billion, which was primarily because of
(B) when the company had lost $7.4 billion, primarily resulting from
(C) when the company lost $7.4 billion, primarily because of
(D) which is when the company lost $7.4 billion, and that was primarily because of
(E) which is when the company lost $7.4 billion, primarily resulting from

AnsC)

我想问的是(C)when the company lost .....中的when到底是修饰谁??
2001? or 1992?
照句意来看
            2001年是1992年以来第一年亏损的年度
            所以when应该是修饰2001啰?
可是我手上的语法详解却是说when修饰1992...感觉怪怪的
            
另外(D)(E)which is when the company lost...中的when又是修饰谁?
2001? or 1992?

when 是修饰1992年