单项选择题
A.Run the command chlogin -shell "csh"
B.Run the command mkuser -default "SHELL=csh"
C.Edit /etc/passwd and change all "ksh" entries to "csh"
D.Modify the contents of /usr/lib/security/mkuser.default file
单项选择题 Forsecurityreasons，anadministratorisaskedtomodifythesystemtopreventsomeonefromleavingaterminalloggedin.Toenableafiveminutetimeoutforallusers，whatwouldneedtobedonetoaccomplishthistask？（）
单项选择题 WhichactionchangesthedefaulteditorforALLusersonthesystemfromvitoeditofthefollowing？（）
单项选择题 Howdoesasystemadministratoraddanewusertoasystem？（）