A select element represents a control that provides a menu of options. Source: MDN Web Docs
Single
 
Multi
 
array(
    'id'             => 'select_1',
    'type'           => 'select',
    'title'          => 'Select Chosen',
    'options'        => array(
        'bmw'          => 'BMW',
        'mercedes'     => 'Mercedes',
        'volkswagen'   => 'Volkswagen',
        'other'        => 'Other',
    ),
    'default_option' => 'Select your favorite car',     // optional 
    'default'     => 'bmw',                             // optional 
    'class'       => 'chosen',                          // optional 
    'prepend'     => 'dashicons-arrow-down-alt',        // optional, add icon, text before the element
    'append'      => 'dashicons-admin-tools',           // optional, add icon, text after the element
    'attributes' => array(
        'multiple' => 'multiple',                       // optional, create a multi select
        'style'    => 'width: 200px; height: 125px;',   // optional 
    ),
),