Consider the linked-list representation of disjoint sets, where: (1) Each set is represented by a linked list; (2) Each element stores a pointer to the set's representative; (3) UNION(x, y) appends the shorter list to the longer list (union by size); (4) FIND-SET(x) runs in $O(1)$ time. Suppose we start with $n$ singleton sets and perform any sequence of UNION and FIND-SET, using union by size. Which of the following statements is correct?