A group of 2m - 1 routers are interconnected in a centralized binary tree. With router at each tree node. Router I communicates with router J by sending a message to the root of the tree. If root then sends the message back down J, the mean path length will be

A group of 2m - 1 routers are interconnected in a centralized binary t

1.	A group of 2m - 1 routers are interconnected in a centralized binary tree. With router at each tree node. Router I communicates with router J by sending a message to the root of the tree. If root then sends the message back down J, the mean path length will be
A.	2 (m - 2)
B.	2 (2m - 1)
C.	m - 1
D.	(2m - 1)/mJ
Answer» B. 2 (2m - 1)