user: Question: What is the StuffitX value that has a Stuffit of Unknown, LHA/LZH of Yes, and Unknown ISO/CD image?
Columns: ['gzip', 'bzip2', 'LHA/LZH', 'StuffIt', 'StuffIt X', 'ISO/CD Image']
Types: ['text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['Yes [14 ]', 'Yes [14 ]', 'No', 'No', 'No', 'No']
SQL:

assistant: SELECT "StuffIt X" FROM "Table" WHERE "StuffIt" = 'Unknown' AND "LHA/LZH" = 'Yes' AND "ISO/CD Image" = 'Unknown';