If a function is friend of a class, which one of the following is wrong?

Question

Admin · Accepted Answer

Friend functions are members of a class.

Admin · Answer

A function can only be declared a friend by a class itself.

Admin · Answer

Friend functions are not members of a class, they are associated with it.

Admin · Answer

It can have access to all members of the class, even private ones.

Q. If a function is friend of a class, which one of the following is wrong?