Question: What was a previous unoffical name for the high performance variant of Audi's compact executive car?
Sentence (from "Audi A6"): Audi's internal numbering treats the A6 as a continuation of the Audi 100 lineage, with the initial A6 designated as a member of the C4-series, followed by the C5, C6, and the C7.
Relevant evidence: No