I found it in FCE practice tests book (Use of English)
"One day you will have to stand up / face for the truth about yourself.
I would say the correct answer is stand up.
Thanks
Not being sure what is expected, I think the most natural sentence for me is "One day you will have to face the truth about yourself."
I agree but that doesn't appear to be an option in the original question. It would have to say "... you will have to face for the truth about yourself". On that basis, "... you will have to stand up for the truth about yourself" is the only grammatically correct answer but it's not very natural and I don't know what they wanted it to mean.
That is why I rejected it.
Unless I'm missing something, it's a poor question.