user: Question: What is the winning score of the tournament on 16 May 1993?
Columns: ['Date', 'Tournament', 'Winning score', 'Margin of victory', 'Runner(s)-up']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['26 Jul 1987', "U.S. Women's Open", '–3 (72-70-72-71=285)', 'Playoff', 'JoAnne Carner , Ayako Okamoto']
SQL:

assistant: SELECT "Winning score" FROM "Table" WHERE "Date" = '16 May 1993';