Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Primary Sclerosing Cholangitis ?
    ### Response:
    PSC is a disease that damages and blocks bile ducts inside and outside the liver. Bile is a liquid made in the liver. Bile ducts are tubes that carry bile out of the liver to the gallbladder and small intestine. In the intestine, bile helps break down fat in food.
    