To achieve the worst possible height in a binary search tree $($BST$),$ you need to insert elements in either strictly increasing or strictly decreasing order. This will result in a degenerate tree, which is essentially a linked list.For example, inserting the sequence $[1,2,3,4,5]$ into a BST will create a tree where each node has only a right child, leading to a height of $4($which is for elements$).$Similarly, inserting the sequence $[5,4,3,2,1]$ will create a tree where each node has only a left child, also resulting in a height of $4.$In general, for a sequence of elements, the worst$-$case height of the BST is $.$