**Core Concept**
Liver transplantation is a lifesaving treatment for patients with end-stage liver disease (ESLD), which is characterized by irreversible liver dysfunction and cirrhosis. The liver's critical functions, including detoxification, protein synthesis, and metabolic regulation, are severely impaired in ESLD patients.

**Why the Correct Answer is Right**
The most common indication for liver transplantation in ESLD patients is cirrhosis with decompensated liver function. Decompensated liver function is marked by the presence of one or more complications, such as ascites, variceal hemorrhage, or hepatic encephalopathy. Liver transplantation is typically considered when these complications cannot be controlled with medical management and the patient's quality of life is significantly impaired.

Cirrhosis leads to liver dysfunction due to the accumulation of scar tissue, which disrupts normal liver architecture and function. The liver's inability to clear toxins, produce clotting factors, and regulate metabolism contributes to the development of complications associated with ESLD. The decision to transplant is based on the severity of liver dysfunction and the presence of complications that cannot be managed medically.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because liver transplantation is not typically performed for acute liver failure, which is a medical emergency that requires immediate treatment. The most common causes of acute liver failure are acetaminophen overdose and viral hepatitis.

**Option B:** This option is incorrect because liver transplantation is not a standard treatment for primary sclerosing cholangitis (PSC), a chronic liver disease characterized by inflammation and scarring of the bile ducts. While liver transplantation may be considered in some cases of PSC, it is not the most common indication for liver transplantation.

**Option C:** This option is incorrect because liver transplantation is not typically performed for non-cirrhotic portal hypertension, a condition characterized by increased pressure in the portal vein without liver cirrhosis. Non-cirrhotic portal hypertension may be caused by conditions such as portal vein thrombosis or schistosomiasis.

**Clinical Pearl / High-Yield Fact**
Liver transplantation is a highly effective treatment for ESLD, with a 5-year survival rate of approximately 80-90%. The most common causes of liver transplantation are hepatitis C, hepatitis B, and non-alcoholic steatohepatitis (NASH).

**Correct Answer:** C.