A cronjob must run at least every 11 minutes. The job may take up to 7 minutes to complete, and there mustn’t be two jobs at the same time. Which crontab line solves the problem?

A.
*/8 * * * * myjob

B.
*/9 * * * * myjob

C.
*/10 * * * * myjob

D.
*/11 * * * * myjob

E.
*/12 * * * * myjob

Explanation/Reference:
A) 0,8,16, … 48,56,0,8 … there are only 4 minutes between 56 and 0
B) 0,9,18,… 45,54,0,9 … there are only 6 minutes between 54 and 0
D) 11,22, … 44,55,0 … there are only 5 minutes between 55 and 0
E) 12 is already too much