Why can't I choose DUTCH as language for my surveys

Why can't I choose DUTCH as language for my surveys

Hi

I offer surveys to my csutomers in three languages: dutch, french and english. I have my surveys professionnaly translated from dutch source language into french and english. I know how to offer respondents theire preferred language choice..

But it seems there is no way to thick DUTCH as the native survey language in survey settings????  See survey.jpg.
So now people get this choice English (or any other language in the dropdown but no DUTCH) | French | English. See survey2.jpg