Answer:

A window.

Container Classes

A GUI program consists of a collection of graphical components that are all placed inside one or more windows. The components are contained by the window. A container is an object that can hold other GUI components. Visually, a container is an area of the screen and the objects it contains are shown as smaller areas within it.

In Java terminology, a window (such as the browser window you are looking at) is a container. The buttons, sliders, icons and other GUI components are contained (by the container).

QUESTION 8:

Do you think that a container can contain another container?