What is the output of the following code?

public class Test $\{$

public static void main$($String$[]$ args$)\{$

Object o$1=$ new Object$()$;

Object o$2=$ new Object$()$;

System.out.print$(($o$1==$ o$2)+""+($o$1.$equals$($o$2)))$;

$\}$

$\}$

a$.$

false false

b$.$

true true

c$.$

false true

d$.$

true false