Final answer:
The cross-section shape of a square pyramid is typically a square if cut parallel to the base, or a trapezoid if cut from the base to the opposite vertex.
Step-by-step explanation:
The cross-section shape of a square pyramid depends on the plane through which the cross-section is taken. If you make a cross-section parallel to the base of the square pyramid, the shape will be a square. However, if the cross-section is made through the middle, from the base to the opposite vertex (the apex), it will consequently be a trapezoid. This is because the sides of the pyramid will appear shortened as they converge towards the apex, creating shorter top sides on your cross-section, thus forming a trapezoid. The options of rectangle or rectangle with chamfered corners are not typical cross-sections for a square pyramid. An octahedron, which can be visualized as two square pyramids with their bases attached, would have a square cross-section if cut through the middle of the shared base.