Look at the block structure and pick, from four choices, what it looks like from the front, the right side, and the top.
Front view: from left to right, each column shows as many squares as its tallest stack. A taller stack behind a shorter one still shows.
Right side view: you look from the right, so the front row appears on the left and the back row on the right.
Top view: a floor map of the cells that have at least one block. The front row is at the bottom.