What is the 'natural' way of returning one instance of a class as an object of another through a constructor

Assuming that in situation X I want to return a class instance through variables, I see no problem doing this:

$rs = "\" .$Namespace . "\" . $Class;
$inst = new $rs();
return $inst;

In an example, where I want to have the option of using a class object in another class to modify something that would not be modified by default, something like an abnormal thing, then I would have this:

class Dados{

   public function dado1(){
      return [1 => 'dado1',2 =>'dado2',3 =>'dado3'];
   }

   public function dado2(){
      return [4 => 'dado4',5=>'dado5',6 =>'dado6'];
   }

}    
class Componentes {

   public function junta($array1,$array2){
       return array_merge($array1,$array2);
   }

   public function transformaEmJson($array){
      return json_encode($array);
   }

}
class DevolverAsDuasClassesComOConstrutor {

    public $Componentes;
    public $Dados

    public function __construct() {

        $inst1 = new Dados();
        $this->Dados = $inst;
        $inst1 = new Componentes();
        $this->Componentes = $inst;
    }

}

$class = new DevolverAsDuasClassesComOConstrutor();

$dado1 = $class->Dados->dado1();
$dado2 = $class->Dados->dado2();
$arr = $class->Componentes->junta($dado1,$dado2);
$json = $class->Componentes->transformaEmJson($arr);
echo $json;

The idea is to use a class without methods, to return other instances, and to use this class with the instances as an extensible class, since it will contain the instances of what is being done.