**Core Concept**
The question tests the understanding of venous anatomy, specifically the connections between the external and internal jugular veins. The **jugular veins** are major blood vessels that return deoxygenated blood from the head to the heart.

**Why the Correct Answer is Right**
The correct connection between the external and internal jugular vein is facilitated by the **common facial vein** or directly through other smaller veins, but a key connection is through the **retromandibular vein** which indirectly connects the external jugular to the internal jugular vein via the facial vein and then to the internal jugular.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect as it does not accurately describe a direct or indirect connection between the external and internal jugular veins.
**Option B:** This option is also incorrect because it does not specify a known anatomical connection between these two veins.
**Option C:** This choice is incorrect as the described connection does not anatomically link the external to the internal jugular vein.

**Clinical Pearl / High-Yield Fact**
A key point to remember is that the internal jugular vein is a major vessel for return of blood from the brain and face, and its connections can be crucial in understanding the spread of infection or the pathway for certain medical procedures.

**Correct Answer:** D. Common Facial Vein.