question: What is the StuffitX value that has a Stuffit of unknown, LHA/LZH of yes, and unknown ISO/CD image?
answer: SELECT stuffit AS X FROM table_name_26 WHERE stuffit = "unknown" AND lha_lzh = "yes" AND iso_cd_image = "unknown"
context: CREATE TABLE table_name_26 (stuffit VARCHAR, iso_cd_image VARCHAR, lha_lzh VARCHAR)