To prevent a specific user from scheduling tasks with at, what should the administrator do?

A. Add the specific user to /etc/at.allow file.

B. Add the specific user to [deny] section in the /etc/atd.conf file.

C. Add the specific user to /etc/at.deny file.

D. Add the specific user to nojobs group.

E. Run the following: atd –deny [user].