Which statement about bubble sort is true?

Bubble sort is a simple sorting algorithm that operates by repeatedly stepping through the list to be sorted, comparing each pair of adjacent elements. If the elements are in the wrong order, the algorithm swaps them. This process is repeated until no more swaps are needed, indicating that the list is sorted.

The key characteristic of bubble sort is this comparison and swapping of adjacent elements, which is fundamental to how the algorithm operates. The algorithm continues to traverse the list until a complete pass is made without any swaps, confirming that the entire list is sorted. This method of sorting demonstrates the step-by-step approach of bubble sort, leading to its characteristic 'bubbling' of the largest unsorted elements to their correct position in each iteration.

In contrast to this method, the other statements do not accurately describe bubble sort's functionality or characteristics. While bubble sort is simple, it is not the fastest sorting algorithm available, nor does it require pre-sorted data or segment the list for sorting. Hence, the statement about comparing and swapping adjacent elements is indeed true and reflects the fundamental operation of the bubble sort algorithm.