单选题：A B+ tree of order 3 with 21 numbers has at most ___ nodes of de

A B+ tree of order 3 with 21 numbers has at most ___ nodes of degree 2. @[D](3)

A. 1
B. 5
C. 6
D. 7



A.1
B.5
C.6
D.7


答案：D