user: Question: What is the tournament surface at Aptos?
Columns: ['Date', 'Tournament', 'Surface', 'Opponent in the final', 'Score']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['July 13, 1998', 'Aptos', 'Hard', 'Takao Suzuki', '6–7, 6–3, 6–2']
SQL:

assistant: SELECT "Surface" FROM "Table" WHERE "Tournament" = 'Aptos';