单选题：Insert 9, 8, 7, 2, 3, 5, 6, 4 into an initially empty AVL tree.

Insert 9, 8, 7, 2, 3, 5, 6, 4 into an initially empty AVL tree. Which one of the following statements is FALSE? @[D](3)

A. 7 is the root
B. 2 and 5 are siblings
C. there are 2 nodes whose BF are -1
D. 3 is the parent of 4



A.7 is the root
B.2 and 5 are siblings
C.there are 2 nodes whose BF are -1
D.3 is the parent of 4


答案：D