通常用普鲁卡因作为局部浸润麻醉是因其（）
A.毒性小，作用时间长
B.毒性小，作用起效快
C.毒性小，麻醉效果强
D.穿透力强
E.以上都不对
参考答案：C
Only when your identity has been checked ____________. [ ]
A. you are allowed in
B. you will be allowed in
C. will you allow in
D. will you be allowed in
花粉产生于
A．花药
B．花丝
C．子房
D．胚珠
