女性，40岁。胫骨上端肿瘤切除后拟行膝关节置换，选择哪种假体为好（）。

A.髁限制型人工膝关节

B.铰链式人工膝关节

C.铰链旋转式人工膝关节

D.球臼式人工膝关节

E.后稳定型人工膝关节

Tom _____ to his friend’s birthday party, but he was too busy yesterday.  [ ]

A. must have gone                  

B. may have gone  

C. can have gone                    

D. could have gone