Which THREE statements about crontab are true?
A.
Every user may have their own crontab.
B.
Changing a crontab requires a reload/restart of the cron deamon.
C.
The cron daemon reloads crontab files automatically when necessary.
D.
hourly is the same as "0 * * * *".
E.
A cron daemon must run for each existing crontab.
Explanation:
From the man pages:
Additionally, cron checks each minute to see if its spool directory’s modtime (or the modtime on /etc/crontab) has changed, and if it has, cron will then examine the modtime on all crontabs and reload those which have changed. Thus cron need not be restarted whenever a crontab file is modified. Note that the crontab(1) command updates the modtime of the spool directory whenever it changes a crontab.