The _________ look on his face suggested that what the monitor said was ___________.

A．puzzling; puzzled

B．puzzled; puzzled

C．puzzled; puzzling

D．puzzling; puzzling

在B超检查中，中等水平回声见于（）

A.肝实质

B.骨骼

C.胆结石

D.肌腱

E.血管壁