What really makes this tricky is that you are viewing the image on the cardboard from the opposite direction from how you would view the sun directly. If you saw the image from the back side of the cardboard (if it were a piece of ground glass, for example), the image would be completely reversed. The bite would appear to be at 10:30 in that case.

But you are looking at a sort of shadow from the other side of the cardboard, so the image is a mirror image that reverses right and left. Therefore, the shadow image that you see on the cardboard has a bite out of the 1:30 position. Top and bottom have been inverted, but left and right are not.

The answer is (a) 1:30.

This conclusion is verified by actual photographs taken during a recent eclipse.