Consider the following stack operations. What will be

Solution

The stack operates on a Last-In, First-Out (LIFO) principle. The operations are executed as follows:

1. stack.push(5) → Stack: [5]
2. stack.push(10) → Stack: [5, 10]
3. stack.pop() → Removes the top element 10 . Stack: [5]
4. stack.push(15) → Stack: [5, 15]
5. stack.push(20) → Stack: [5, 15, 20]
6. stack.pop() → Removes the top element 20 . Stack: [5, 15]
7. stack.push(25) → Stack: [5, 15, 25]

Thus, the final stack content is [5, 15, 25] . Why Other Options Are Wrong Option A: [5, 10, 25] This sequence assumes the second pop() operation does not occur. However, 20 is removed during the second pop() . Option C: [5, 10, 15] This sequence omits the addition of 25 in the final push() operation. Option D: [5, 15, 20] This sequence retains 20 in the stack, but 20 is removed during the second pop() . Option E: [5, 25] This sequence ignores the intermediate pushes of 15 and retains only 5 and 25 , which is incorrect.