Among the following idioms（ ）is an idiom adverbial in nature.
A、flesh and blood
B、up in the air
C、as poor as a church mouse
D、tooth and nail
【正确答案】：D
【题目解析】：本题考查副词性习语。tooth and nail：竭尽全力地；副词性习语。flesh and blood：亲骨肉；名词性习语。up in the air：悬而未决的：形容词性习语。as poor as a church mouse：一贫如洗：形容词性习语。
