穿刺活检后是否须留观()

①无须留观

②细针活检后无须留观

③18G活检后留观2小时左右

④＞18G针活检后留观2小时左右

⑤＞18G针活检后须住院留观

A．①④

B．②③⑤

C．①③⑤

D．②④

E．①②③④

There is something we need to________before the meeting begins. [ ]

A. clear up  

B. clear away

C. clean up  

D. clean out