user: Question: What opponent used the KO method, and a 6-0 record?
Columns: ['Res.', 'Record', 'Opponent', 'Method', 'Event', 'Round', 'Time']
Types: ['text', 'text', 'text', 'text', 'text', 'real', 'text']
Sample row: ['Win', '17-3', 'Carlo Prater', 'Decision (split)', 'Shine: Lightweight Grand Prix', 3.0, '5:00']
SQL:

assistant: SELECT "Opponent" FROM "Table" WHERE "Method" = 'KO' AND "Record" = '6-0';