**Core Concept**
Total Parenteral Nutrition (TPN) is a method of delivering essential nutrients intravenously to patients who are unable to consume food orally. The process involves infusing a mixture of carbohydrates, proteins, fats, vitamins, and minerals directly into the bloodstream. This method can lead to various complications due to the high concentration of nutrients and the risk of infections associated with central venous access.

**Why the Correct Answer is Right**
The most common complication associated with TPN is **Infection**. This is mainly due to the use of central venous catheters, which provide a portal of entry for pathogenic microorganisms. The risk of infection is further increased by the contamination of the TPN solution and the administration of the solution through a central line. The most common types of infections associated with TPN are catheter-related bloodstream infections (CRBSIs) and catheter-related urinary tract infections (CRUTIs).

**Why Each Wrong Option is Incorrect**
**Option A:** **Metabolic Bone Disease** is a potential complication of TPN, but it is not the most common complication. This condition occurs due to the imbalance of calcium and phosphorus in the TPN solution, leading to bone demineralization.
**Option B:** **Hepatic Dysfunction** can occur in patients receiving TPN, but it is not the most common complication. This condition is often associated with the use of high concentrations of glucose in the TPN solution, which can lead to insulin resistance and liver damage.
**Option C:** **Cardiovascular Disease** is not a direct complication of TPN. However, patients receiving TPN may be at risk of cardiovascular disease due to the high caloric intake and the potential for lipid emulsions to contribute to atherosclerosis.

**Clinical Pearl / High-Yield Fact**
When administering TPN, it is essential to follow strict aseptic technique to minimize the risk of infection. This includes using sterile equipment, preparing the TPN solution in a laminar airflow hood, and verifying the patency of the central line before administration.

**Correct Answer: C. Hepatic Dysfunction.**