What best describes a freestanding wall that is unsecured at the top?

A freestanding wall that is unsecured at the top is best described as a cantilever wall. Cantilever walls are designed to extend out from a supporting structure without additional support or anchoring at the upper portion. This design allows the wall to stand on its own while being fixed at the bottom, relying on its weight and structural properties to maintain stability.

In contrast, a load-bearing wall is a structural element that supports vertical loads from above, which typically requires stability and secure anchoring at the top. A shear wall is specifically designed to resist lateral forces, providing rigidity and stability to a structure during events like earthquakes or high winds, which again necessitates specific anchoring methods. A parapet wall is a barrier that extends above the roofline, often serving as a safety feature or decorative element, and is typically secured at the top to prevent collapse.

The characteristics of a cantilever wall emphasize its structural independence at the top, making it the most accurate description for a freestanding wall that lacks top support.