What will be the output of the following PHP code?

 <?php  $cars = array(Volvo, BMW, Toyota, Honda, Mercedes, Opel);
print_r(array_chunk($cars, 2));
?> 

A.

Array ( [0] => Array ( [1] => Volvo [2] => BMW ) [1] => Array ( [1] => Toyota [2] => Honda ) [2] => Array ( [1] => Mercedes [2] => Opel ) )

B.

Array ( [1] => Array ( [1] => Volvo [2] => BMW ) [2] => Array ( [1] => Toyota [2] => Honda ) [3] => Array ( [1] => Mercedes [2] => Opel ) )

C.

Array ( [0] => Array ( [0] => Volvo [1] => Volvo ) [1] => Array ( [0] => BMW [1] => BMW ) [2] => Array ( [0] => Toyota [1] => Toyota ) )

D.

Array ( [0] => Array ( [0] => Volvo [1] => BMW ) [1] => Array ( [0] => Toyota [1] => Honda ) [2] => Array ( [0] => Mercedes [1] => Opel ) )