[SC悬赏令] 毕出21套第4套sc求解答

15.Despite the criticism in the early 1890's that if journalists use pictures the intellectual quality of  publications would diminish, by the late 1890's photographs were found in most newspapers and magazines.

(A)        that if journalists use pictures the intellectual quality of publications would diminish,

(B)        that if journalists use pictures it will diminish the intellectual quality of publications,

(C)        that the use of pictures by journalists would diminish the intellectual quality of publications,

(D)        of the intellectual quality of publications being diminished by the use of pictures by journalists,

(E)        of the use of pictures by journalists diminishing the intellectual quality of publications,

毕出的解释如下（个人感觉不太好理解）：

A．        that引导的是criticism的同位语从句，解释说明criticism的内容。同位语从句里面，“if journalists use pictures”是条件状语从句，意为“如果记者使用照片”，修饰句子“the intellectual quality of publications would diminish”（质量会下降）。此时，“使用照片”是质量下降的条件，至于谁最终使得质量下降，没有交待。但结合后半句“photographs were found in most newspapers and magazines”（照片还是在大部分报纸杂志上被发现了），可以推断出一定是“使用照片”这件事使得质量下降，所以“使用照片”做diminish的主语更合理。

C．        正确。整句话字面意思为“尽管有个批评（使用照片会使得刊物的质量下降），但照片还是在大部分报纸杂志上被发现了”。

求解A,C选项中同一结构充当diminish 的条件状语和主语时有什么语义上的区别？

还是说区别AC的不是这个考点，求大神解答