— Is David          honest and organized boy?

— Yes, that is why he was chosen to be the president of the Students’ Union.

A．a

B．an

C．the

D．/

脊柱骨折常见的并发症有

A．呼吸系统感染

B．泌尿系统感染

C．压疮

D．骨质疏松

E．应激性溃疡