It's not, because in a standard B-tree all the leaf nodes are at exactly the same depth, whereas in a binary tree they are not in general, unless the binary tre

It's not, because in a standard B-tree all the leaf nodes are at exactly the same depth, whereas in a binary tree they are not in general, unless the binary tree is balanced with exactly 2N leaves. This difference occurs because a B-tree can have interior nodes that aren't completely full, whereas a binary tree's interior nodes have exactly 2 children.