Judging from his face_______ there was a confident smile, we knew that he didn’t lose heart.

A．in which

B．from which

C．by which

D．on which

患者，男，30岁，3个月前因外伤一前牙脱落，有临时活动义齿修复，现要求固定修复。口腔检查：缺失，间隙可，牙槽嵴无明显吸收，近中切角缺损，叩（一）无松动，牙冠正常，叩（一），X线片，行完美根管治疗，全身状况良好

最合适的治疗方案是（）。

A.种植修复与冠修复

B.桩核修复与双端固定桥

C.单端固定桥

D.弹性义齿与冠修复

E.以上都不是