题目

. ________ when the boulders suddenly disappeared. A. So relieved we felt                         B. How relieved we felt C. What a relief we were feeling         D. How we felt relieved 答案：B有人在医院做过化验后检验结果为“缺铁性贫血”，这里“缺铁”是指缺（　　）A．铁元素B．铁分子C．铁原子D．铁离子