同一句子中代词指代相同问题

孤独狂欢

在同一个句子中, 两个代词it的指代一定要相同的。

除非一个it做形式主语，另一个it指代XX，那不算歧义

isaxi

下面这道题就是这种情况：
102.    (29983-!-item-!-188;#058&004080)

Recent breakthroughs in technology have made it possible that high-definition digital video cameras are able to capture material with a degree of fidelity that nearly compares to 35-millimeter film and to project it digitally in theaters with no resulting loss of image quality.

(A) it possible that high-definition digital video cameras are able to capture material with a degree of fidelity that nearly compares to
(B) it possible to have high-definition digital video cameras that can capture material at a degree of fidelity almost like that with
(C) it possible for high-definition digital video cameras to capture material with a degree of fidelity nearly comparable to that of
(D) possible high-definition digital video cameras that can capture material at a degree of fidelity almost like
(E) possible high-definition digital video cameras able to capture material with a degree of fidelity that nearly compares to that with

正确答案是C。第一个it确实是形式主语。
因为也见过Prep破解的反例：即使形式主语也不能有两个it。
所以，我自己总结就是：比较对象不对等是绝对错误。这种情况的it不是绝对错误。