Top MCQs on Algorithms | DSA Quiz for Beginners

Insertion sort takes linear time when the input array is sorted or almost sorted (maximum 1 or 2 elements are misplaced). All other sorting algorithms mentioned above will take more than linear time in their typical implementation.

Hence Option (A) is correct

The worst-case complexity of the Selection Sort algorithm is O(n^2), where n represents the number of elements in the input array.

Selection Sort works by repeatedly finding the minimum element from the unsorted portion of the array and swapping it with the element at the current position. In the worst-case scenario, each iteration requires scanning the remaining unsorted portion of the array to find the minimum element, resulting in nested loops.

In the worst case, the number of comparisons made by Selection Sort is approximately (n-1) + (n-2) + (n-3) + ... + 2 + 1, which can be simplified to (n^2 - n) / 2. This gives a time complexity of O(n^2).

Hence option (B) is correct.

After analyzing the complexity of all sorting algorithms, O(nlogn) is the best complexity considered.

For more reference:

https://www.geeksforgeeks.org/time-complexities-of-all-sorting-algorithms/

Hence Option (B) is correct.

Because the Average and worst-case time complexity of Bubble sort is  n^2. Bubble Sort repeatedly compares adjacent elements and swaps them if they are in the wrong order until the entire array is sorted.
for more reference:

https://www.geeksforgeeks.org/time-complexities-of-all-sorting-algorithms/

Hence Option (C) is correct.

In its typical implementation, the Quick Sort algorithm is not a stable sorting algorithm. On the other hand, algorithms like Merge Sort and Insertion Sort are stable sorting algorithms, meaning that the relative order of equal elements is maintained during the sorting process.

Hence Option (A) is correct.

In the best case, the key might be present at the first index. So the best case complexity is O(1)

Hence Option (C) is correct.

Binary Search is defined as a searching algorithm used in a sorted array by repeatedly dividing the search interval in half.  and reduce the time complexity to O(log N).

Hence Option (A) is correct.

The binary search can only be applied if the array is in sorted order.

Hence Option (B) is correct.

The bitwise  Negate operator is a unary operator (works on only one operand)., and is and used to find 2's complement.

Hence Option (C) is correct.

The bitwise complement operator is a unary operator (works on only one operand),  except this all of the above are binary Operand operators.

Hence Option (D) is correct.