This is also called the Sally-Anne test, and it usually involves two hiding places. It's formulated like this:

Sally puts her ball in box A and leaves. While she's away, Anne moves the ball from box A into box B. When she returns, where does Sally look for her ball?

Correctly answering this question doesn't rely on tracking where the ball is, but tracking where Sally thinks the ball is. Hence, autistic kids tend to flunk this test by answering "box B" when the correct answer is "box A".