The correct way to echo when using AJAX with MVC (CodeIgniter)

I have a form that is submitted to the method submit_ajaxwhen submitted via AJAX. Now that I get it as an AJAX request, I want to return a JSON object.

In this case, I have two options. What could be considered the right way, following the MVC pattern?

Option 1 Echo from the controller

class StackOverflow extends CI_Controller 
{   
    public function submit_ajax()
    {
        $response['status'] = true;
        $response['message'] = 'foobar';
        echo json_encode($response);
    }
}

Option 2 Configure a view that receives data from the controller and echoes.

class StackOverflow extends CI_Controller
{
    public function submit_ajax()
    {
        $response['status'] = true;
        $response['message'] = 'foobar';
        $data['response'] = $response;
        $this->load->view('return_json',$data);
    }
}

//return_json view
echo json_encode($response);