Briefing Zend Knowledge

What is the output of the following code?

What is the output of the following code? class Number { private $v; private static $sv = 10;
public function __construct($v) { $this->v = $v; } public function mul() { return static function
($x) { return isset($this) ? $this->v*$x : self::$sv*$x; }; } } $one = new Number(1); $two =
new Number(2); $double = $two->mul(); $x = Closure::bind($double, null, ‘Number’); echo

$x(5);

A.
5

B.
10

C.
50

D.
Fatal error