Step 1: Focus on which liver disease most often pushes a child to transplantation rather than on the general list of indications. Step 2: Biliary atresia destroys the bile ducts in infancy, and even after a Kasai procedure many children progress to end-stage cirrhosis, making it the dominant paediatric transplant diagnosis. Step 3: Because it presents so early and so commonly with failing bile drainage and failure to thrive, biliary atresia tops the indication list for children. Step 4: The other options are valid causes of liver failure but trail behind in children, so the answer is biliary atresia. \[\boxed{\text{Biliary atresia}}\]