[问答] Which of the following statements are true about alpha-beta pruning？以下关于alpha–beta剪枝的陈述哪些是正确的？ A.lpha–betpruning is to decrease the number of nodes that are evaluated by the minimax algorithm in its search tree．Alpha–beta剪枝旨在减少其搜索树中由minimax算法评价的节点数量。 B.Alpha–beta pruning is to increase the number of nodes that are evaluated by the minimax algorithm in its search tree．Alpha–beta剪枝旨在增加其搜索树中由minimax算法评价的节点数量。 C.Alpha–beta pruning is to eliminate large parts that are evaluated by the minimax algorithm in its search tree．Alpha–beta剪枝旨在消除其搜索树中由minimax算法评价的大部分。 D.Alpha–beta pruning is to adlarge parts that are evaluateby the minimax algorithm in its search tree．Alpha–beta剪枝旨在添加其搜索树中由minimax算法评价的大部分。