Geometry

Question Analysis:
This question involves identifying which shape does not fit the definition of a pyramid.
The main focus is to detect non-pyramids among look-alikes.

Key Concept Explanation:
Pyramids have one polygonal base and triangular faces that meet at one apex. Prisms have two bases and rectangular sides.

Step-by-Step Solution:
A: Square base + triangle sides + apex → pyramid
B: Triangle base + triangle sides + apex → pyramid (tetrahedron)
C: Two bases → prism
D: Hexagon base + 6 triangles + apex → pyra...