Thank you for asking this question, I just learned something!
I did not know the answer, so I went to look at the code (question/format/gift/format.php), and the answer is much more interesting than I expected.
By default, it is Moodle auto-format, however, you can write something like
[html]<p>Here is some HTML question text</p>
That is, with the format you want in square brackets. The format names recognised are moodle, html, plain and markdown.
Quiz
What is the default text format for GIFT?
This discussion has been locked so you can no longer reply to it.