94高考一題英文文法 - 高考

請問一下英文高手下面這題：

問題：_____ regarded as his masterpiece, his war painting was left in the
warehouse for a whole decade.

(A)as (B)Though (C)與(D)都明顯不合故不列


請問答案應是哪一個呢? 萬分感謝。

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