**Core Concept**
The nasal cavity is supplied by multiple arteries that arise from the external carotid and internal carotid arteries. The anterior part of the nasal septum and lateral nasal wall receive their blood supply primarily from branches of the sphenopalatine artery, while the posterior part is supplied by branches of the anterior and posterior ethmoidal arteries.

**Why the Correct Answer is Right**
The posterior ethmoidal artery supplies the posterior ethmoidal cells and the superior part of the nasal septum. However, it does not contribute significantly to the blood supply of the anterior part of the nasal septum and lateral nasal wall, which are the common sites for epistaxis (nosebleeds). The sphenopalatine artery, through its branches, including the greater palatine artery and anterior ethmoidal artery, provides the primary blood supply to these areas.

**Why Each Wrong Option is Incorrect**
**Option A:** The greater palatine artery is a branch of the sphenopalatine artery and plays a significant role in supplying blood to the anterior part of the nasal septum and lateral nasal wall, making it a correct option for aerial supply to the epistaxis area.

**Option B:** The anterior ethmoidal artery is a branch of the ophthalmic artery and supplies the anterior ethmoidal cells and the anterior part of the nasal septum, making it a correct option for aerial supply to the epistaxis area.

**Option D:** The sphenopalatine artery is the primary artery responsible for supplying blood to the anterior part of the nasal septum and lateral nasal wall, making it a correct option for aerial supply to the epistaxis area.

**Clinical Pearl / High-Yield Fact**
The Kiesselbach's plexus, located in the anterior part of the nasal septum, is a common site for epistaxis due to its rich blood supply from branches of the sphenopalatine artery.

**✓ Correct Answer: C. Posterior ethmoidal**