A female patient has a removed oral mass; biopsy shows acanthosis and hyperkeratosis. What is the MOST likely diagnosis?

Acanthosis (thickened spinous layer) and hyperkeratosis (thickened keratin layer) are classic histological findings of an oral papilloma (squamous papilloma), often caused by HPV. Pyogenic granuloma shows vascular proliferation histologically. Peripheral giant cell granuloma shows multinucleated giant cells. Fibroma shows dense fibrous connective tissue.