Object-oriented_2-13 multiple choice questions

The correct option for the following code to run is () (choose one)

class Test{
Public $str='abc';
}
$a=new Test();
$b=$a;
$a->str='456';
var_dump($a) ;
echo "</br>";
var_dump($b) ;

class Test{
Public $str='abc';
}
$a=new Test();
$b=$a;
$a->str='456';
var_dump($a) ;
echo "</br>";
var_dump($b) ;
// object(Test)#1 (1) { ["str"]=> string(3) "456" } 
// object(Test)#1 (1) { ["str"]=> string(3) "456" }