Study the following method carefully which can be related to a certain class, decide what does it do? public void Unknown(E item) { Node node = new Node(item): Nodeparent=null. current char d; if(root == null) root = node: else current=root: while(current i= null) { parent = current if (current.data if(dw') parent.left=node: else parent.right - node: A Remove a node which its data is equal to item from a binary tree Insert a node in a binary tree with item as its data Insert a node in a binary search tree with item as its data Remove a node which its data is equal to item from a binary search tree