This example demonstrates a conditional SVG rendering inside a React component. A circle is drawn at the center of a 960×500 viewport; because the constant R is set to 400, the ternary operator in JSX chooses the red circle with radius 150 instead of the green one with radius 400. The code uses React’s `ReactDOM.render` and JSX to produce the SVG output, with inline styling and a production build of React 16.10.0.