Answer:
B. Rectangle
Step-by-step explanation:
We are given that,
<em>'The plane intersects the rectangular pyramid'.</em>
<h3>'A rectangular pyramid is a three-dimensional object with rectangular as the base and triangles as the sides'.</h3>
<em>So, a plane intersecting a rectangular pyramid horizontally will be parallel to the rectangular base.</em>
Thus, the cross-sectional plane will be a rectangle.
Hence, option B is correct.