Ah beastie, and I was tryin so hard to make this easy enough to understand for ya, so let's try it one more time.
Under which 3 presidents did you serve while in the Marines?
Since you said "3 different admins" that would by nature mean (unless you mispoke) that this would be under 3 different presidents, since each president, even if reelected is still only considered one administration.
So .. give 'er another go eh ?:>
You may optionally give an explanation for why this post was reported, which will be sent to the moderators along with the report. This can help the moderator to understand why you reported the post.