一个比较题，大家看看吧

Thomas Eakins's powerful style and his choices of subject--the advances in modern surgery,

the discipline of sport, the strains of individuals in tension with society or even with

themselves--was as disturbing to his own time as it is compelling for ours.

(A) was as disturbing to his own time as it is

(B) were as disturbing to his own time as they are

(C) has been as disturbing in his own time as they are

(D) had been as disturbing in his own time as it was

(E) have been as disturbing in his own time as

这题看不明白，我选E，答案是B。为什么？？这是什么比较结构，比较什么DD。

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