You can find the files for this example in the lesson2-focus/05-radio-group directory.

Using the ARIA Authoring Best Practices doc (either version 1.0 or version 1.1) find the radio pattern and implement support for the Down Arrow and Right Arrow pattern.

Note: The 1.0 version of the doc refers to this as a "Radio Button" whereas the 1.1 version of the doc refers to this as a "Radio Group".

You'll want to work in the radiogroup.js file to implement your keyboarding support.