The five items: A, B, C, D and E are pushed in a stack,one after the other starting from A. The stack is popped four times and each element is inserted in a queue. Then two elements are deleted from the queue and pushed back on the stack. Now one item is popped from the stack. The popped item is.

To determine which item is popped from the stack, let's go through the given scenario step by step:

1. The five items A, B, C, D, and E are pushed into a stack, one after the other starting from A. This means that the last item pushed onto the stack is E.

2. The stack is popped four times, which means that the last four items pushed onto the stack (E, D, C, and B) are popped out of the stack in reverse order (B, C, D, and E).

3. Each popped item is then inserted into a queue. Therefore, the queue now contains the elements B, C, D, and E, in the order they were popped from the stack.

4. Two elements are deleted from the queue. Let's assume the deletion is done from the front of the queue. Therefore, the two elements deleted from the queue are B and C. The queue now contains the elements D and E.

5. The two deleted elements (B and C) are then pushed back onto the stack. Since the elements are pushed onto the stack in the reverse order they were deleted from the queue, C is pushed first, followed by B.

6. Now, one item is popped from the stack. Since B was the last item pushed onto the stack, it will be the first item popped from the stack.

Therefore, the item popped from the stack is B.

The correct answer is B.

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