The answer is letter D - 5.
Since 0,1,2,3 represents late departure and 4,5,6,7,8,9 represents an on-time departure, we will have to identify the simulations having 4 to 9 numbers only in all of the three flights. In this case, 769 (fourth), 555 (eight), 658 (twelveth), 694 (thirteenth), 968 (seventeenth).
So there are 5 simulations out of 20 who had an on-time departure for all of the three flights.