[单选题]abstract class Shape {int a,b;public Shape(int aa, int bb) {a=aa; b=bb;}abstract public double area（ ）;}class Rectangle extends Shape {public Rectangle(int aa, int bb) {super(aa,bb);}public double area（ ） {return a*b;}}class Triangle extends Shape {public Triangle(int aa, int bb) {super(aa,bb);}public double area（ ） {return a*b/2;}} public class XXK3 {public static void main(String[] args) {Shape x,y;x=new Rectangle(10,20);y=new Triangle(10,15);System.out.println(x.area（ ）+, +y.area（ ）);}}

A.200.1, 75.1
B.200.0, 75.0