In a stack, where can elements be added or removed?*1 pointa. Only at the topb. Only at the bottomc. At both the top and bottomd. Anywhere in the stack

Answer

In a stack data structure, elements can only be added or removed from one end, which is referred to as the "top" of the stack. This characteristic of stacks follows the Last In, First Out (LIFO) principle, meaning the most recently added element is the first to be removed.

To clarify the options:

1. Only at the top (Correct Answer) - This is true as elements can be pushed onto the stack at the top and popped off from the top.
2. Only at the bottom - This is incorrect because a stack does not allow access to the bottom for adding or removing elements.
3. At both the top and bottom - This is also incorrect for a standard stack. In certain variations (like a deque), elements can be added or removed from both ends, but that does not define a traditional stack.
4. Anywhere in the stack - This is incorrect as it suggests that elements can be added or removed from arbitrary positions, which goes against the stack's operational design.

Final Answer

a. Only at the top