Which building element is typically described as a tapering structure that comes to a point at the top?

A spire is accurately described as a tapering structure that comes to a point at the top. It is often found on top of towers and roofs of buildings, especially in religious architecture such as cathedrals and churches. Spires are not only functional architectural elements, aiding in the stability of the structure, but they also serve an aesthetic purpose, drawing the eye upward and instilling a sense of aspiration or reaching towards the heavens.

In contrast, the other choices represent different architectural features. A flying buttress is a support element that extends from an exterior wall to a distant support, often seen in Gothic architecture, but it does not taper to a point. A pediment is a triangular upper section of a building's facade, typically found above a colonnade or portico, and is primarily decorative without a tapering form. A frieze is a horizontal band that decorates the upper part of a wall or building, often adorned with sculptures or reliefs, and does not have the tapering shape characteristic of a spire.

Thus, the identification of a spire as a tapering structure is correct based on its distinctive form and common usage in certain architectural styles.