As insert url's in email in cakephp 3?

I want to send an email through the class Cake\Mailer\Email; and when inserting a link <a href="url"></a> insert another url that includes the transport host configured in bootstrap.php

My action on the controller:

$email = new Email();
        $email
            ->setTemplate('credito_generado')
            ->setEmailFormat('html')
            ->setTo($email)
            ->setCc(EMAIL_SALIENTE)
            ->setSubject('Credito generado')
            ->setViewVars([
                'c_nombre' => $nombre,
                'c_paterno' => $apellido_paterno,
                'c_materno' => $apellido_materno,
                'c_plazo' => $plazo,
                'c_monto' => number_format($total, DECIMALES),
                'c_id' => $id
            ]);
        $result_email = $email->send();
        $this->log('RESULT_EMAIL: '.print_r($result_email, true), LogLevel::DEBUG);

In src \ Template \ Email \ html \ vista.ctp I only print the variables and a link with:

<a href="<?= \Cake\Routing\Router::fullBaseUrl().'/nexumclub/creditos/tabla-pdf/'.$c_id ?>">VER</a>