**Core Concept**
The external nose is a complex anatomical structure composed of bone, cartilage, and soft tissue. The nasal bones and cartilages work together to provide support, shape, and function to the nose, including breathing, olfaction, and facial aesthetics.

**Why the Correct Answer is Right**
The correct answer highlights the presence of two nasal bones in the external nose. The nasal bones are paired, thin, flat bones that form the bridge of the nose. They are derived from the first and second branchial arches during embryonic development. These bones provide a firm base for the cartilaginous structure of the nose and play a crucial role in maintaining the nasal septum. The two nasal bones are connected by the inter nasal suture, which is a fibrous joint.

**Why Each Wrong Option is Incorrect**
**Option A:** The upper 1/3 of the external nose is actually cartilaginous, not bony. The lower 1/2 of the nose contains the cartilaginous nasal septum and the lower lateral cartilages.
**Option B:** The lower 1/3 of the external nose is primarily made up of the alar cartilages, which are a complex series of cartilages that provide shape and support to the nostrils, not just a single cartilage.
**Option C:** There are actually three lateral cartilages in the external nose: the upper lateral cartilage, the lower lateral cartilage, and the alar cartilage. These cartilages work together to provide support and shape to the nostrils.

**Clinical Pearl / High-Yield Fact**
It's essential to remember that the nasal bones are the only paired bones in the face, and their presence or absence can be a crucial diagnostic clue in radiological imaging, especially in cases of nasal trauma or congenital anomalies.

**✓ Correct Answer: D. Two nasal bones**