—I hear a traffic accident happened yesterday. Was it terrible ?        

—Yes. A car _____ and all the people in it were badly hurt. But luckily, none of them was killed.      [ ]

A. fell over

B. fell behind

C. fell off

D. fell down to

掣痛的病机是

A．血瘀

B．气滞

C．筋脉失养或阻滞不通

D．寒邪阻络

E．阴虚火旺