**Core Concept**
The nerve supply of the tip of the nose is provided by a specific branch of the trigeminal nerve, which is responsible for the sensory innervation of the face.

**Why the Correct Answer is Right**
The correct answer is the external nasal branch of the ophthalmic division of the trigeminal nerve (V1). This branch arises from the ophthalmic nerve (V1), which is the first division of the trigeminal nerve. The external nasal branch innervates the skin of the tip of the nose, providing sensation to this area. This is a critical anatomical detail, as it highlights the complex innervation of the face by the trigeminal nerve.

**Why Each Wrong Option is Incorrect**
* **Option B:** The inferior orbital nerve is a branch of the maxillary nerve (V2), which is the second division of the trigeminal nerve. It does not innervate the tip of the nose.
* **Option C:** The buccal branch of the mandibular nerve (V3) is responsible for the innervation of the cheek and the buccal mucosa, not the tip of the nose.
* **Option D:** The orbital branch of the maxillary nerve (V2) provides sensory innervation to the orbital contents, but not the tip of the nose.

**Clinical Pearl / High-Yield Fact**
To remember the nerve supply of the tip of the nose, recall that it is innervated by a branch of the ophthalmic division of the trigeminal nerve (V1). This is a critical anatomical detail, as it highlights the complex innervation of the face.

**✓ Correct Answer: A. Ext nasal branch of ophthalmic division of**