有如下程序 public class Test int a,b; Test ( ) a = 100; b = 200; Test(int x, int y) a = x; b = y; public static void main(String args[]) Test Obj1 = new Test(12,45); System.out.println( a = Obj1.a+ b = +Ob31.B) ; Test Obj1 = new Test(); System.out.println( a = Obj1.a+ b = +Obj1.B) ; 程序的运行结果为( )。
A．a=100 b=200
a=12 b=45
B．a=12 b=45
a=100 b=200
C．a=12 b=200
a=100 b=45
D．a=100 b=45
a=12 b=200