Don't quote Spock on this, you're being illogical. I understand these quizzes are tweaked to take people out of the running, and it seems like you've somewhat gamed the system to try and take the prize. Nothing wrong with that, Starfleet often engaged in such subterfuge.
NTA, you're trying to beef out a decent squad and don't want any redshirts. She just happens to be Ensign Ricky.
But you probably did hurt her feelings. That might be worth sitting down and explaining that the squad has become more competitive, and she... crap no, that would be a dick move.
Wow, you find yourself in quite the dilemma Captain. It's become an asshole, or find a gentle way to remove her from the squad.
Still not as bad as the Kobayashi Maru.