CORRECT TEXT
Deny to all users except root to run cron schedule.

Answer:

Explanation:
1. vi /etc/cron.allow
root
or
vi /etc/cron.deny
Write all user name to deny.
/etc/cron.allow, /etc/cron.deny file is used to control users to allow or deny. If /etc/cron.allow file is
created only that users are allowed to run cron schedule. Another way to deny to users is
/etc/cron.deny write all user name on single line.