**Question:** A 60-year-old male patient presented to the OPD with complaints of a mass in the epigastric region with no other complaints. On examination, the mass was found to be pulsatile. USG abdomen was done. CT abdomen The doctor did a procedure. For the procedure the doctor accessed an artery in the lower limb and opened a sheath to expose the artery. Which of the following structures is enclosed inside that sheath: -

A. Aorta
B. Common Femoral Artery
C. External Iliac Artery
D. Umbilical Artery

**Correct Answer:** **D. Umbilical Artery**

**Core Concept:**

The correct answer is D, the umbilical artery, because it is a blood vessel in the lower limb that has a similar procedure performed on it, similar to the one described in the question. The other options are incorrect for the following reasons:

A. Aorta: It is not a blood vessel in the lower limb; instead, it is a large artery in the thorax that supplies blood to the lower limbs.

B. Common Femoral Artery: This artery is also in the lower limb, but it is not the artery that would have a procedure performed on it.

C. External Iliac Artery: This artery is also a lower limb artery, but it is not the artery typically chosen for the described procedure.

**Why the Correct Answer is Right:**

The correct answer, D, umbilical artery, is chosen because it is a blood vessel located in the lower limb, which is a common location for procedures such as the one described in the question. In this case, the procedure involves accessing the artery through an incision in the skin and opening a sheath to expose the artery. The umbilical artery is a suitable choice for this procedure due to its location and the possibility of performing such an operation on it.

**Why Each Wrong Option is Incorrect:**

A. Aorta: This artery is located in the thorax and not in the lower limb, making it an incorrect choice for the described procedure.

B. Common Femoral Artery: Similarly, as mentioned earlier, this artery is located in the lower limb but is not the artery chosen for the described procedure.

C. External Iliac Artery: Although this artery is in the lower limb, it is not the artery typically targeted for the described procedure.

**Why the Correct Option is Right:**

The correct answer, D, umbilical artery, is right because it is a blood vessel situated in the lower limb, making it a suitable site for the described procedure. By accessing the artery through an incision in the skin and opening a sheath, the doctor can expose and manipulate the umbilical artery. This process is commonly used in clinical practice to study or monitor blood flow parameters in the limb or to access the artery for diagnostic or therapeutic purposes.

**Why Each Wrong Option is Incorrect:**

A. Aorta: This artery is located in the thorax and not in the lower limb, making it an incorrect choice for the described procedure.

B.