Task: Explanation
Input (English): Ben Camey Wallace (born September 10, 1974) is an American retired professional basketball player. A native of Alabama, Wallace attended Cuyahoga Community College and Virginia Union University and signed with the Washington Bullets (later Wizards) as an undrafted free agent in 1996. In his NBA career, Wallace played with the Washington Bullets/Wizards, Orlando Magic, Detroit Pistons, Chicago Bulls and Cleveland Cavaliers. Question: Who was the head coach during the 1999 season in which Ben Wallace was traded from the Washington Wizards? Answer: Doc Rivers
Output (English):  A native of Alabama, Wallace attended Cuyahoga Community College and Virginia Union University and signed with the Washington Bullets later Wizards as an undrafted free agent in 1996.