What methods does the class Class$2$ have to override?

interface interace$1\{$

public void method$1()$;

$\}$

interface interface$2\{$

public void method$2()$;

$\}$

abstract class Class$1$ implents Interface$1\{\}$

class Class$2$ extends Class$1$ implents Interface$2\{\}$

a$)$ only method$1$

b$)$ only method$2$

c$)$ method$1$ and method$2$

d$)$None of the methods