What does the while $(!$emptyl$)$ loop in the stack

destructor accomplish?

$$ a$.$ It adds new elements to the stack before clearing it$.$

O b$.$ It deallocates all dynamically allocated nodes in the stack, preventing memory

leaks.

$$ c$.$ It copies the stack contents to a temporary stack before deallocating.

$$ d$.$ It iterates through the stack nodes and sets their data to default values.