Using jQuery to select default value in populated dropdown

I have a dropdown that is being populated with titles from a custom post type. Using the solution found on this page: http://etzelstorfer.com/en/create-dynamic-ninja-forms-lists-post-types/

What I need is to be able to set a certain post ID to be the default value in the dropdown. I’ve tried setting ‘selected’ to the post ID, but no luck there.

Any advice is appreciated! Full jQuery below:

function prepopulate_forms($data) {
    if($data['label']=='Location') {  
        $args = array(
            'post_type' => 'locations',
            'orderby' => 'name',
            'order' => 'ASC'
        );
        $query = new WP_Query( $args );
        if ( $query->have_posts() ) {
            $data['list']['options']=array();
            while ( $query->have_posts() ) {
                $query->the_post();
                $data['list']['options'][] = array(
                        'label' =>  get_the_title(),
                        'value' =>  get_the_title(),
                        'calc'  =>  null,
                        'selected' => null
                    );
            }
        } 
        wp_reset_postdata();
    }
    return $data;
}
add_filter('ninja_forms_field','prepopulate_forms');