Which of the following are init systems used within Linux systems?

AS OF 9-2-15 AT 11AM CDT THE EXAM IS VALID IN THE USA I PASSED WITH A SCORE OF 800/800 EVERY QUESTION WAS WORD FOR WORD EVEN THE ANSWER CHOICES WERE NOT SCRAMBLED OR WORDED DIFFERENTLY I SUGGEST GOING TO AIOTEST KING AND LOOKING OVER THAT AS WELL IT HAS A FEW OF THE MISSING QUESTIONS THAT THIS DOES NOT HURRY UP AND TAKE IT BEFORE IT CHANGES NOW !!!!!!!!!!!!