—I am sure Mary will win the first prize in the final.

—I think so. She______ for it for months.

A．is preparing

B．was preparing

C．had been preparing

D．has been preparing

下列哪项骨折是稳定骨折

A．桡骨远端青枝骨折
B．尺桡骨双骨折
C．肱骨干斜骨折
D．肱骨髁上骨折伸直型
E．股骨颈骨折内收型