In JavaFX, a RadioButton is a user interface control that allows the user to select one option from a group of options. Here's an example of how to create and use RadioButton controls:

import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.RadioButton;
import javafx.scene.control.ToggleGroup;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;

public class MyJavaFXApp extends Application {
    
    @Override
    public void start(Stage primaryStage) {
        // Create a group of radio buttons
        ToggleGroup group = new ToggleGroup();
        
        RadioButton radioBtn1 = new RadioButton("Option 1");
        radioBtn1.setToggleGroup(group);
        
        RadioButton radioBtn2 = new RadioButton("Option 2");
        radioBtn2.setToggleGroup(group);
        
        RadioButton radioBtn3 = new RadioButton("Option 3");
        radioBtn3.setToggleGroup(group);
        
        // Put the radio buttons in a layout container
        VBox vbox = new VBox(10, radioBtn1, radioBtn2, radioBtn3);
        
        // Create a scene and set it on the stage
        Scene scene = new Scene(vbox, 300, 250);
        primaryStage.setScene(scene);
        
        // Show the stage
        primaryStage.show();
    }
    
    public static void main(String[] args) {
        launch(args);
    }
}

In this example, we create a group of RadioButton controls by creating a ToggleGroup object and setting it as the toggle group for each RadioButton. We then put the RadioButton controls in a VBox layout container, create a scene with the VBox, and set the scene on the stage. When the user clicks on a RadioButton, it will become selected and the previously selected RadioButton in the group will become deselected.