**Core Concept**
Clinical aniridia is a rare congenital disorder characterized by the partial or complete absence of the iris. This condition is often associated with mutations in the PAX6 gene, which plays a crucial role in the development of the eye and brain. The PAX6 gene is a transcription factor that regulates the expression of other genes involved in eye development.

**Why the Correct Answer is Right**
Clinical aniridia is often associated with other eye abnormalities, such as coloboma, microphthalmia, and cataract. These abnormalities occur due to the disruption of the normal development of the eye, which is controlled by the PAX6 gene. In addition, individuals with clinical aniridia are at an increased risk of developing glaucoma, which is a condition characterized by increased intraocular pressure.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because clinical aniridia is often associated with other eye abnormalities, such as coloboma, microphthalmia, and cataract.
**Option B:** This option is incorrect because clinical aniridia is not typically associated with a normal ocular development.
**Option C:** This option is incorrect because clinical aniridia is often associated with an increased risk of developing glaucoma.

**Clinical Pearl / High-Yield Fact**
It is essential to note that clinical aniridia is a rare condition, but it is often associated with other eye abnormalities and an increased risk of developing glaucoma. Therefore, individuals with clinical aniridia require regular eye examinations and monitoring to prevent vision loss.

**Correct Answer:** D.