Question

When does the worst case of binary search occur?

• A. When the element is present at the middle of the array
• B. When the element is present at the first position
• C. When the element is not in the array or is found at the last level of recursion
• D. When the element is at the second position

Hint:

Binary search performs well in sorted arrays but reaches its worst case when it must check every possible division down to a single element.

Answer 1

The Correct Option is C

Binary search operates by repeatedly dividing the search space in half at each step. The worst-case scenario occurs when the search must continue until the smallest possible subarray is reached.
- If the target element is absent from the array, the search will proceed until all elements have been checked.
- Likewise, if the element is located only at the final level of recursion, it means the maximum number of comparisons was required.
- The worst-case time complexity is \( O(\log n) \), which happens when the array is continuously halved until a single element remains.
Conclusion: The worst case for binary search arises when the element is either missing from the array or is found only at the deepest level of recursion.