I remember that ____ took part in the ball party had a wonde

I remember that ____ took part in the ball party had a wonderful time.?为什么选择all that
I remember that ____ took part in the ball party had a wonderful time.
选项是A.all that B.all C.all which D.all what
你们选择什么呢
我的分析是,这是个定语从句,先行词that 后面要+引导词
虽然前面有all后面要加that 但是前面已经有了that 不是为了避免重复选择which嘛?