**Core Concept**
The question requires knowledge of the venous drainage of the face, specifically the connection between the facial vein and the cavernous sinus. The facial vein is a superficial vein that drains the facial region, and it ultimately empties into the internal jugular vein. However, it has a unique connection with the cavernous sinus, which is a dural venous sinus located within the skull.

**Why the Correct Answer is Right**
The correct answer is the superior ophthalmic vein, which connects the facial vein to the cavernous sinus. This connection is significant because it allows for the spread of infection or inflammation from the face to the intracranial structures. The superior ophthalmic vein is a valveless vein that allows for bidirectional flow of blood between the facial vein and the cavernous sinus. This unique anatomy is responsible for the spread of infections such as cavernous sinus thrombosis.

**Why Each Wrong Option is Incorrect**
**Option A:** is incorrect because it is not a known connection between the facial vein and the cavernous sinus.
**Option B:** is incorrect because it is a different venous structure altogether.
**Option C:** is incorrect because it is not the correct vein that connects the facial vein to the cavernous sinus.

**Clinical Pearl / High-Yield Fact**
The connection between the facial vein and the cavernous sinus via the superior ophthalmic vein is a classic example of a "danger zone" in medicine, where infection or inflammation can spread rapidly from the face to the intracranial structures.

**Correct Answer: C. Superior ophthalmic vein.**