下列程序的输出结果为( )。
public class Reentrant
public synchronized void a()
b();
System.out.println("here I am, in a()");
public synchronized void b()
System.out.println("here I am, in b()");
public static void main(String args[ ])
Reentrant r=new Reentrant();
r.a();
A．here I am, in a()/here I am, in b()
B．hereI am, in b()/here I am, in a()
C．here I am, in a()
D．here I am, in b()