What is a common characteristic of a triangular head shape?

A triangular head shape is typically characterized by a narrow forehead that gradually widens towards the jaw. This feature creates a distinct outline where the forehead is the smallest part of the head, while the jawline is broader, giving it a triangular appearance. This shape is often seen in individuals whose facial structure is more prominent at the lower portion of the face.

The options that describe other shapes include features that do not align with the defining characteristic of a triangular shape. For instance, a wide forehead combined with a narrow chin would imply a shape more akin to a heart or inverted triangle. Equal proportions throughout would correspond to a more oval or round face, and roundness in all areas suggests a circular face rather than the defined angles and proportions characteristic of a triangular head shape. Thus, the description of a narrow forehead leading to a wide jaw perfectly aligns with the defining traits of a triangular head shape.