array(
    'type'  => 'select',
    'value' => 'choice-3',
    'attr'  => array( 'class' => 'custom-class', 'data-foo' => 'bar' ),
    'label' => __('Label', '{domain}'),
    'desc'  => __('Description', '{domain}'),
    'help'  => __('Help tip', '{domain}'),
    'choices' => array(
        '' => '---',
        'choice-1' => __('Choice 1', '{domain}'),
        'choice-2' => array(
            'text' => __('Choice 2', '{domain}'),
            'attr' => array('data-foo' => 'bar'),
        ),
        array( // optgroup
            'attr'    => array('label' => __('Group 1', '{domain}')),
            'choices' => array(
                'choice-3' => __('Choice 3', '{domain}'),
                // ...
            ),
        ),
    ),
    /**
     * Allow save not existing choices
     * Useful when you use the select to populate it dynamically from js
     */
    'no-validate' => false,
)