public function alterSelectbox(MethodInvocation $invocation)
    {
        $helper = $invocation->getThis();
        list($fieldName, $options, $attributes) = array_pad($invocation->getArguments(), 3, null);
        $options = $options === null ? [] : $options;
        $attributes = (array)$attributes;
        $attributes = $this->_addClass($helper, $attributes, 'form-control');

        $this->setProperty($invocation, 'arguments', [$fieldName, $options, $attributes]);

        return $invocation->proceed();
    }