Element select

select =>

array:15 [
  "class" => "Drupal\Core\Render\Element\Select"
  "provider" => "core"
  "id" => "select"
  "#input" => true
  "#multiple" => false
  "#sort_options" => false
  "#sort_start" => null
  "#process" => array:2 [
    0 => array:2 [
      0 => "Drupal\Core\Render\Element\Select"
      1 => "processSelect"
    ]
    1 => array:2 [
      0 => "Drupal\Core\Render\Element\Select"
      1 => "processAjaxForm"
    ]
  ]
  "#pre_render" => array:1 [
    0 => array:2 [
      0 => "Drupal\Core\Render\Element\Select"
      1 => "preRenderSelect"
    ]
  ]
  "#theme" => "select"
  "#theme_wrappers" => array:1 [
    0 => "form_element"
  ]
  "#options" => []
  "#value_callback" => array:2 [
    0 => "Drupal\Core\Render\Element\Select"
    1 => "valueCallback"
  ]
  "#type" => "select"
  "#defaults_loaded" => true
]