The correct answer is A. In Tkinter event handling, an event object contains information about the event that occurred. One of its useful attributes is widget, which refers to the actual widget object that caused or received the event. This is not merely the widget’s name as text; it is a reference to the widget instance itself. That means the event handler can inspect or manipulate the widget directly, for example by reading its configuration or changing its displayed value. Option B and option D are incorrect because they describe a name, not an object reference. Option C is unrelated, since run() is not part of Tkinter event object semantics.