I'm sure others will find this more amusing than I did. Perhaps if two of the words are too vulgar to allow on the quiz, then you might consider using a different question. Just a grandmother's point of view.
The Four F's are a very useful mnemonic in both biology and psychology. They're the basic drives that animals have. They're the activities which evolution shapes animals to be good at. And they're the behaviors that get triggered when an animal is under stress. I don't think they should be left out just because they're slightly off-color. (I've seen the fourth F sometimes given as "Fornication", to make it less obvious that a vulgar word has been suggested. Would you prefer that I display it that way? Obviously I have to accept all three common variants--"Reproduction", "Mating", and "Fornication"--regardless of which one I choose to display.)
I understand all about animal drives and have no problem with discussing them. My only problem with using that question here is that there are very young people who take quizzes on this site. I can't imagine any middle school or high school science teacher teaching students the "Four F" mnemonic (at least I hope the "F-bomb" hasn't become that commonplace.) It's a very offensive word to most of my generation. I'm no prude, but I personally prefer a little higher standard. Just my two-cents' worth, (if it's worth that much.)