What word is missing from the following SQL statement?

　　update tablename ____ fieldname='value' where id=909;

　　ANSWER: SET,SET

　　Which of the following configuration files should be modified to set default shell variables for all users?

　　A./etc/bashrc

　　B./etc/profile

　　C.~default/.bash_profile

　　D./etc/skel/.bashrc

　　E./etc/skel/.bash_profile

　　Answer: B