對(duì)下圖所示的二叉樹(shù)進(jìn)行中序遍歷(左子樹(shù)、根、右子樹(shù))的結(jié)果是 ()。A.2 5 3 4 6 1 B.2 5 3 4 1 6 C.2 6 5 4 1 3 D.2 6 4 5 3 1