In a child with acute liver failure, the most important abnormal serum biochemical test that indicates poor prognosis:

C. Increasing prothrombin time(Ref: Nelson's 20/e p 1967)Hepatic synthetic function is reflected in serum albumin and protein levels and in the PT or INRUnresponsiveness of PT to vitamin K suggests severe hepatic diseasePersistently low levels of factor VII are evidence of a poor prognosis in fulminant liver diseaseSerum aminotransferase activities do not correlate well with the severity of the illness.