单选题 It was kind of ______ to see a revolution achieve its goals at relatively little cost.

【正确答案】 D

【答案解析】此处的形容词breathtaking意思是“令人激动的”；melancholy表示“忧郁的”；painstaking表示“令人痛苦的”；ecstatic表示“欣喜若狂的”，根据题意选项D最合适。