How many times will the function counter() be executed in the following code?

How many times will the function counter() be executed in the following code? function
counter($start, &$stop) { if ($stop > $start) { return; } counter($start–, ++$stop); } $start = 5;
$stop = 2; counter($start, $stop);

A.
4

B.
5

C.
6

D.
3