—Must I go through the radiation (辐射) check when I come back from Japan at the airport these days?

—Yes, you ______. [ ]

A. can

B. may

C. might

D. must

在互联网上很多公用的FTP服务器都可以随意进出，这些公用的FTP服务器称为（）FTP服务器

A.通用

B.免费

C.实名

D.匿名