题目

空气中含量较多且化学性质不活泼的气体是 A．氮气                       B．氧气                       C．稀有气体                   D．二氧化碳 答案：AHe wasn't feeling well, ________ he went to lie down on the bed. [　　] A．thatB．soC．as a result ofD．but