**Core Concept**
The patient's symptoms of pain, redness, watering, and light intolerance suggest an acute inflammatory condition affecting the anterior segment of the eye. This presentation is characteristic of a specific type of corneal infection.

**Why the Correct Answer is Right**
The patient's symptoms are consistent with a diagnosis of **Bacterial Keratitis**, an infection of the cornea caused by bacteria such as Staphylococcus aureus, Pseudomonas aeruginosa, or Streptococcus pneumoniae. The infection leads to inflammation, pain, and photophobia due to the release of pro-inflammatory cytokines and the activation of the immune response. The corneal epithelium becomes compromised, allowing bacteria to invade the stroma and cause tissue damage.

**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because **Viral Keratitis** typically presents with a more gradual onset of symptoms, including blurred vision, eye pain, and decreased visual acuity. Viral infections such as herpes simplex keratitis are more common in immunocompromised patients.
* **Option B:** This option is incorrect because **Contact Lens Keratopathy** is a specific type of corneal injury caused by prolonged contact lens wear, leading to corneal ulcers and inflammation. While it can cause similar symptoms, the presentation is typically associated with contact lens use.
* **Option D:** This option is incorrect because **Iritis** is an inflammation of the iris and is typically characterized by eye pain, redness, and photophobia. However, iritis is usually associated with a more gradual onset and is not typically accompanied by corneal ulcers or keratitis.

**Clinical Pearl / High-Yield Fact**
In cases of suspected bacterial keratitis, it is essential to perform a thorough ocular examination, including corneal scrapings for bacterial culture and sensitivity testing. Early treatment with topical antibiotics can help prevent vision loss and improve outcomes.

**Correct Answer:** C.