Bubble sort can be improved by using inner loop while required (i.e. swapping element while required) , otherwise inner loop should skip
(A) Doing both way sort is not an efficient solution , As if we do left to right increasing order sorting , then right to left decreasing order.
(B) Though quick sort has time complexity O(n log n) in avg case which is better than bubble sort O(n2), but that is not needed for getting better version of bubble sort. Actually here we are using quick sort and then again bubble sort , which is not improving time or space complexity of bubble sort
(C)Swapping in separate array will increase space complexity of bubble sort
So, Answer will be (D)