MSFinals-1413

A 33-year-old former intravenous (iv) drug abuser presents to outpatient clinic with abnormal liver function tests (LFTs) at the recommendation of his general practitioner. Although he is not experiencing any symptoms, a physical examination reveals hepatomegaly measuring 4 cm. Further blood tests confirm that he is positive for hepatitis C, with a significantly elevated viral load of hepatitis C RNA. What would be the most crucial investigation to determine the appropriate management of his hepatitis C?