When I think about that question, I think about questions that would be harder for me (white caucasian) than somebody from another "race" or culture. That is easy: for example imagine selecting some kind of image puzzles involving kanjii symbols, or telling apart chinese faces. They are just images, right, so no bias? But it will be much more easy to tell them apart for somebody with a chinese background than for me. If such questions exists that are biased against me, it seems at least very plausible that other questions could be biased against other "races" and cultures. Another example I read about is how different cultures see the drawing of a box (a 3d wireframe). Apparently in western cultures people would see it as a drawing of a 3d box, whereas some poor test takers in Africa just saw a 2d drawing. This was then interpreted as Africans being less intelligent, when really they were just as correct as the people who saw the 3d shape. It just wasn't such a common meme where they lived to draw 3d shapes like that.