Populate a Drop down from Database

I am new to CI. I am trying to populate a Country from Database to a Drop down in View . After passing a Array Data how do i show in drop down.

Following are the Code:
1. controller Country

Code:

public function get_country_dropdownlist()
   {
      $data['country'] = $this->Country_model->get_country_dropdownlist();
      //print_r($data);
      //die;
       $this->load->view('country_list_view', $data);
   }

2. Model

Code:

public function get_country_by_id($country_id)
   {
        //return $this->db->insert_id();
       $this->db->select("country_id,country_name");
       $this->db->from('country');
       $this->db->where(['country_id'=>$country_id]);
       $query = $this->db->get();
       return $query->result();
   }

3.View

Code:

 <?php echo form_dropdown('country_id',$data['country']); ?>