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Radio buttons are sometimes used when the field requires a selection from a limited set of options. The options are all simultaneously visible on the panel, each of which is associated with a round button that is either selected (i.e., it contains a blue dot) or deselected (i.e., it is empty). Only one of the buttons can be selected at a time; selecting one deselects whichever was previously selected. The option associated with the selected button is considered by the panel to be the chosen option. Radio buttons serve a similar purpose to drop downs. While they are less common, they are most often used when the selected option itself influences another part of the panel,; for example, when another field may or may not be editable, depending on which radio button was selected.