It was ______ he saw the doctor coming out of the emergeney room with an expression as grave as a judge _______ he realized the seriousness of his wife’s illness.
A、not until…that
B、after…when
C、until…then
D、before…that
【正确答案】：A
【题目解析】：句意：直到他看到医生从急诊室里走出来，表情严肃得像法官一样，他才意识到妻子病情的严重性。