In the following code, which classes can be instantiated?
abstract class Graphics {
abstract function draw($im, $col);
}
abstract class Point1 extends Graphics {
public $x, $y;
}
function _construct($x, $y) {
$this->x = $x;
$this->y = $y;
}
function draw($im, $col) {
lmageSetPixel($im, $this->x, $this->y, $col);
}
class Point2 extends Point1 {}
abstract class Point3 extends Point2 {}
A . Graphics
B . Point1
C . Point2
D . Point3
E . None, the code is invalid
Answer: C