The running time of quick sort depends heavily on the selection of Select one:Pivot elementNo of inputs Arrangement of elements in array  Size of elements

The running time of quick sort heavily depends on the following factors:

1. Pivot Element: The pivot element is the element around which the array is partitioned. If the pivot is chosen such that it always divides the array into two halves, the time complexity will be the best, i.e., O(n log n). However, in the worst case, if the pivot is the smallest or the largest element, the time complexity will be O(n^2).

2. Number of Inputs: The number of inputs or the size of the array also affects the running time of quick sort. The more elements there are to sort, the longer it will take.

3. Arrangement of Elements in Array: If the elements are already sorted or nearly sorted, quick sort performs poorly with a time complexity of O(n^2). On the other hand, if the elements are randomly arranged, quick sort performs relatively well with an average time complexity of O(n log n).

4. Size of Elements: The size of the elements does not directly affect the running time of quick sort. However, it may affect the time taken to swap elements during the partitioning process. But this effect is usually negligible compared to the other factors.

So, all the options mentioned affect the running time of quick sort to some extent, but the pivot element and the arrangement of elements in the array are the most significant factors.