**Core Concept**
In newborns, unilateral watery discharge from the eye, without edema or chemosis, is often due to a condition where the nasolacrimal duct fails to open, causing a congenital obstruction. This leads to the accumulation of tears in the duct, resulting in a watery discharge.

**Why the Correct Answer is Right**
The correct condition is a **Persistent Nasolacrimal Duct Obstruction (PNDO)**. This occurs when the nasolacrimal duct fails to open at birth, causing the tears to accumulate in the duct. The tears then flow out through the duct, resulting in a watery discharge from the eye. As the duct opens, the discharge typically resolves on its own within the first few weeks of life.

**Why Each Wrong Option is Incorrect**
* **Option A:** **Congenital Glaucoma** typically presents with edema or chemosis, which is not present in this case.
* **Option B:** **Ophthalmia Neonatorum** is an infection of the conjunctiva or cornea, which would present with symptoms such as redness, discharge, and potentially vision loss.
* **Option C:** **Ptosis** is a drooping eyelid, which is not related to a watery discharge from the eye.

**Clinical Pearl / High-Yield Fact**
Newborns with unilateral watery discharge from the eye without edema or chemosis are likely due to a nasolacrimal duct obstruction, which is usually self-resolving within the first few weeks of life.

**Correct Answer: D. Persistent Nasolacrimal Duct Obstruction (PNDO)**