prep上的两个题 代词指代不一致 很纠结

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

答案c    但两个it指代不同  选项中指形式宾语，题干中指material

(A) they imposed a highly organized economic and political system on many different ethnic groups and permitting them

(B) on their imposition of a highly organized economic and political system on many different ethnic groups, who were permitted

(C) because of their imposition of a highly organized economic and political system on many different ethnic groups, who they permitted

(D) on their imposing of a highly organized economic and political system on many different ethnic groups and they permitted them

(E) imposing a highly organized economic and political system on many different ethnic groups, permitting them

答案b   但their指代不一致，选项中their指代incan empire, 未划线部分指ethnic groups

着如何解释呢？  难道一个句子中， 代词可指代不同？

盼解释