Create a dropdown menu of WP Nav Menu links using a <select> wrapper

dropdowns.php

<?php 
  $menuLocations = get_nav_menu_locations(); // Retrieves Menus
  $menuID = $menuLocations['primary']; // Gets the Primary Menu (Change for your Menu Name)
  $primaryNav = wp_get_nav_menu_items($menuID); // Sets up the Foreach Variable
  echo '<select>';
  foreach ( $primaryNav as $navItem ) {
    $link = $navItem->url;
    $title = $navItem->title;
    echo '<option id="'.$link.'">'.$title.'</option>';
  }
  echo '</select>';

  // From here you would use javascript to trigger the page change