**Core Concept**
Kisselbach's plexus, also known as the Little's area, is a vascular network located in the anterior part of the nasal septum. This plexus is primarily responsible for the rich blood supply to the nasal septum and is a common site for epistaxis (nosebleeds).

**Why the Correct Answer is Right**
Kisselbach's plexus is formed by the anastomosis of several branches from the sphenopalatine artery, which includes the septal branches. These septal branches arise from the sphenopalatine artery and supply the nasal septum. The plexus is situated in the anterior part of the nasal septum, just below the vestibule, and is a common site for bleeding due to its rich blood supply and exposed location.

**Why Each Wrong Option is Incorrect**
**Option A:** This option should be a specific branch of the sphenopalatine artery, such as the superior, middle, or inferior nasal septal branch. However, without the correct answer provided, we cannot determine which branch is incorrect. Regardless, the septal branches of the sphenopalatine artery are the primary contributors to Kisselbach's plexus, making this option incorrect if it lists a septal branch.

**Option B:** Since this option is not provided, we cannot comment on its accuracy. However, we can say that any branch not originating from the sphenopalatine artery would not contribute to Kisselbach's plexus.

**Option C:** This option should be another branch of the sphenopalatine artery, such as the posterior septal branch. However, without the correct answer provided, we cannot determine which branch is incorrect. Regardless, the septal branches of the sphenopalatine artery are the primary contributors to Kisselbach's plexus, making this option incorrect if it lists a septal branch.

**Option D:** This option should be another branch of the sphenopalatine artery, such as the anterior or posterior lateral nasal branch. However, without the correct answer provided, we cannot determine which branch is incorrect. Regardless, the septal branches of the sphenopalatine artery are the primary contributors to Kisselbach's plexus, making this option incorrect if it lists a septal branch.

**Clinical Pearl / High-Yield Fact**
Kisselbach's plexus is a common site for epistaxis due to its rich blood supply and exposed location. It is essential to identify and cauterize this area during nasal septal surgery to prevent postoperative bleeding.

**Correct Answer:** D.