Mary has two brothers, ________ are doctors.

A．both of they

B．both of whom

C．both of them

D．whom of both

胸部损伤时，下列哪项错误（）

A.损伤性窒息表现为上半身皮肤、黏膜、末梢、毛细血管淤血

B.广泛性进行性皮下气肿是高压气胸的特征

C.胸部爆震伤是指高压气浪冲击胸部所致肺毛细血管出血、肺水肿

D.多根肋骨骨折不会引起胸壁软化

E.常常合并颅脑、颈部及腹部复合伤