**Core Concept**
The septal cartilage is a key component of the nasal septum, providing structural support to the nose. It is a thin, flexible plate of hyaline cartilage that separates the two sides of the nasal cavity. Understanding the shape of the septal cartilage is essential for diagnosing and treating nasal septal deviations.

**Why the Correct Answer is Right**
The septal cartilage is indeed **quadrilateral** in shape, with four sides that fit snugly into the nasal cavity. This shape allows it to provide maximum support to the nasal passages while minimizing obstruction. The quadrilateral shape is also crucial for maintaining the integrity of the nasal septum, as it helps to distribute the forces of nasal airflow and pressure evenly.

**Why Each Wrong Option is Incorrect**
**Option A:** Triangular shape would not provide the necessary support to the nasal passages, and would likely lead to nasal obstruction.
**Option C:** Oval shape would not fit snugly into the nasal cavity, potentially causing septal deviations.
**Option D:** Hexagonal shape is not anatomically consistent with the structure of the nasal septum.

**Clinical Pearl / High-Yield Fact**
The quadrilateral shape of the septal cartilage is a critical factor in maintaining normal nasal function, and deviations from this shape can lead to nasal septal perforation or other complications. Recognizing the normal anatomy of the nasal septum is essential for diagnosing and treating nasal disorders.

**✓ Correct Answer: B. Quadrilateral**