男，12岁，平素体弱易感冒，最近10天突然高热，体温达39～40℃，伴左大腿肿痛，患肢不愿动，检查：左大腿下段肿胀，压痛(+)，化验：白细胞18×10/L，中性70%，血红蛋白78g/L。

应选择的治疗方法是()

A．切开引流，开放换药

B．切开引流+骨开窗+开放换药

C．切开引流+骨开窗+灌注引流，缝合伤口

D．切开引流，放置灌注管，缝合伤口

E．反复脓肿穿刺，抗生素冲洗

—My teacher told me never to go to school again.

—Sorry to hear that.But were you often late for class?

—___________.

A．I was too late to study

B．Well,I’m afraid I often were 

C．I did enjoy myself

D．I have no idea