Given an array of n elements, what is true about the worst-case time complexity of mergesort and quicksort methods? the worst-case time complexity of mergesort and quicksort is O(n x log n): the worst-case time complexity of mergesort is O(n2) and quicksort is O(n x the worst-case time complexity of mergesort is O(n x log n) and quicksort is o(n2 the worst-case time complexity of mergesort and quicksort is O(n2): log n) O none of the above