From the following code, protected member is f1 is accessible in

class X {
protected:
void f1() {
};
class Y: public X {};
class Z: public Y{};
class P{};
void test() {  }
 
Options:
 

1. X, Y, Z, & P
2. X, Y, Z, P, & test
3. X, Y, Z only
4. X only