Margaret attended a basketball game in a downtown arena in her hometown. After the game, she wanted to ride the bus home. The orange line and the green line buses both stop at the arena. An orange line and a green line bus both left the arena at 9:15pm. Orange line buses are scheduled to leave the arena every 12 minutes. Green line buses are scheduled to leave the arena every 18 minutes. If the buses run on schedule when is the next time an orange line and a green line bus will leave together?A: 9:27 pmB: 9:51 pmC: 10:23 pmD 9:43 pm