求助OG11-51题

51. The Olympic Games helped to keep peace among the pugnacious states of the Greek world in that a
sacred
            truce was proclaimed
during the festival's month.

(A)        
world in that a sacred truce was
proclaimed during the festival's month

(B)        
world, proclaiming a sacred truce during
the festival's month

(C)       
world when they proclaimed a sacred
truce for the festival month

(D)       
world, for a sacred truce was proclaimed
during the month of the festival

(E)        
world by proclamation of a sacred truce
that was for the month of the festival

答案是D，但是for能引导句子吗？我觉得在这里应该是独立主格结构，但如果是独立主格里面的was应该省略呀。

求助

http://forum.chasedream.com/dispbbs.asp?boardid=23&replyid=1692191&id=152023&page=1&skin=0&Star=4

for引导的原因状语从句，给lz一个建议，问OG和GWD的题呢都先搜索旧帖，前人经验无数~~~