单选题 The German general staff made another dangerous concession to what they considered a military necessity. The plan would be______not when countries formally declared war but simply when they ordered mobilization.
【正确答案】 A
【答案解析】解析：句子大意为：德国总参部又对一项他们认为具有军事必要性的计划进行了授权。该项计划只需在他们发布军事动员令的条件下就可以启动而不必等到国家之间正式宣战。在给出的选项中：trigger“激发、启动”：trifle“琐事、浪费”。本题考查形近词辨析以及被动语态。所以，正确答案是A。