C

Typical biopsy findings that prompt immunosuppression in autoimmune hepatitis are interface (piecemeal) hepatitis with dense portal plasma-cell infiltrates, which, together with a young female patient, elevated IgG, positive ANA and good steroid response, best fit autoimmune hepatitis rather than the other listed disorders [Kriese & Heneghan, 2013, PMID 28839695; Francque et al., 2012, PMID 24367228].