A young adults presents with night blindness and tubular vision. On examination, intraocular pressure was observed to be 18 mm and the anterior segment was unremarkable. Fundoscopy showed attenuation of aerioles and waxy pallor of the optic disc with bony corpuscles like spicules of pigmentation in mid peripheral retina. Ring scotomas were observed on perimetry. Which of the following is the most likely diagnosis:

**Core Concept**
The patient's presentation is suggestive of a hereditary condition affecting the retina, characterized by progressive vision loss, night blindness, and specific fundoscopic findings.

**Why the Correct Answer is Right**
The patient's symptoms and fundoscopic findings are consistent with **Retinitis Pigmentosa (RP)**, a group of genetic disorders affecting the retina's ability to respond to light. The attenuation of arterioles and waxy pallor of the optic disc are hallmarks of RP. The mid-peripheral retinal spicules of pigmentation are also characteristic of this condition. Ring scotomas on perimetry further support the diagnosis.

**Why Each Wrong Option is Incorrect**
**Option A:** **Stargardt Disease** is a juvenile macular degeneration that primarily affects the macula, not the peripheral retina, and does not typically present with ring scotomas.

**Option B:** **Leber Congenital Amaurosis** is a rare, inherited condition that affects infants and young children, often presenting with severe visual impairment and nystagmus, not typically observed in this patient.

**Option C:** **Diabetic Retinopathy** can cause peripheral retinal neovascularization and hemorrhages, but the patient's presentation and fundoscopic findings do not support this diagnosis.

**Option D:** **Central Serous Chorioretinopathy (CSC)** is a condition characterized by fluid accumulation under the retina, typically affecting young adults and presenting with central vision loss and a "smokestack" appearance on fundoscopy, not observed in this patient.

**Clinical Pearl / High-Yield Fact**
Retinitis Pigmentosa is a classic example of a hereditary condition that affects multiple systems, including the retina, and is often associated with other systemic abnormalities, such as hearing loss and ataxia.

**Correct Answer: C. Diabetic Retinopathy**

✓ Correct Answer: A. Pigmentary retinal dystrophy