**Core Concept**
Traumatic cataract formation is a common complication following blunt ocular trauma, often resulting in sudden loss of vision. The mechanism involves disruption of the lens fibers, leading to opacity and vision loss. The deep anterior chamber is a key feature that helps narrow down the diagnosis.

**Why the Correct Answer is Right**
The sudden loss of vision in the context of blunt trauma and deep anterior chamber is most likely due to a **traumatic cataract**. The impact disrupts the lens fibers, leading to a cataractous change. The deep anterior chamber is characteristic of a lens dislocation or cataract formation, as opposed to other conditions like hyphema or retinal detachment.

**Why Each Wrong Option is Incorrect**
* **Option A:** This option is not relevant to the scenario described, as it doesn't directly relate to the sudden loss of vision following blunt trauma.
* **Option B:** This option might be tempting, but it doesn't fit the clinical picture of a deep anterior chamber and sudden loss of vision following trauma.
* **Option D:** This option is incorrect, as it's not directly related to the scenario described and doesn't account for the deep anterior chamber.

**Clinical Pearl / High-Yield Fact**
In the context of blunt trauma, a deep anterior chamber with sudden loss of vision is highly suggestive of traumatic cataract formation. Remember the "3 Ts" of ocular trauma: **Trauma, Tension (deep anterior chamber), and Tissue loss (cataract)**.

**Correct Answer: C. Traumatic cataract.**