Transform "The archive had never faced such a backlog" into a formal sentence beginning with Never. Replace [The archive had never faced] to complete: "Never ___ such a backlog."
Richtige Antwort
had the archive faced
Erklärung
Moving never to the front requires the perfect auxiliary to move ahead of the subject, while faced remains the participle. Keeping subject-auxiliary order would not satisfy the formal inversion triggered by fronting.