How to remove an option when choosing another option in Choices.js

I need that when choosing different options, an option from the selection menu removes another - a special option. Value and Label are different for everyone. How to do it in Choices.js?

Sandbox: https://codepen.io/CryNet/pen/GRRQaGN

<form>
    <select id="select" multiple>
        <option value="foo">foo</option>
        <option value="bar1">bar1</option>
        <option value="bar2">bar2</option>
        <option value="bar3">bar3</option>
    </select>
</form>