The I/O devices form the Â Â Â Â Â Â Â Â Â Â Â of the tree structure.

The I/O devices form the Â Â Â Â Â Â Â Â Â Â Â

1.	The I/O devices form the Â Â Â Â Â Â Â Â Â Â Â of the tree structure.
A.	leaves
B.	subordinate roots
C.	left subtrees
D.	right subtrees
Answer» B. subordinate roots