How to make multiple values selected in dropdown in cakephp 3.x

<div class="form-group">
   <?php
   echo $this->Form->input('area', array('label' => false,
       'placeholder' => 'Enter Zone Name',
       'type' => 'select',
       'class' => 'form-control',
       'id'=>'area',
       'multiple' => 'multiple',
       'options' => $areaList)
   );
   ?>
</div>

This is my dropdrop for input type select on edit page.

I just want to know how can I make $arealist values to be shown selected.

I am using Cakephp 3.x. I am new to cakephp 3.x.