**Core Concept**
The underlying principle being tested is the knowledge of anatomical structures involved in the control of bleeding in the abdominal cavity, particularly the **hepatic pedicle** and surrounding structures. The **hepatic pedicle** contains the **portal vein**, **hepatic artery**, and **common bile duct**.

**Why the Correct Answer is Right**
The **free edge of lesser omentum** (also known as the **hepatoduodenal ligament**) contains the **portal triad**. If occluding this area does not stop the bleeding, it suggests the source of hemorrhage is not the **hepatic artery** or **portal vein** within the **hepatic pedicle**. Instead, the bleeding might be coming from a nearby structure that is not controlled by occlusion of the **hepatoduodenal ligament**.

**Why Each Wrong Option is Incorrect**
**Option A:** This choice is incorrect because occluding the **free edge of lesser omentum** should control bleeding from the **hepatic artery** if it is the source.
**Option B:** Similarly, this choice would be controlled by occlusion of the **hepatoduodenal ligament**.
**Option C:** This option might seem plausible but given the context, it's less likely to be the correct choice without further specification.

**Clinical Pearl / High-Yield Fact**
In cases of severe abdominal trauma with suspected hepatic injury, the **Pringle maneuver** (occluding the **free edge of lesser omentum**) can be used to temporarily control bleeding from the **liver** by stopping flow through the **hepatic artery** and **portal vein**. If this maneuver does not stop the bleeding, it may indicate bleeding from other sources such as the **inferior vena cava** or **hepatic veins**.

**Correct Answer:** D. Hepatic vein