C++ Inline Function Interview Question:

Which of followings is/are not false about friend function?

1. It can be called / invoked with class object
2. It has objects as arguments
3. It can have built-in types as arguments
4. It must declared only in public part of a class
5. It does not have this pointer as an argument

a. Only 2,4
b. Only 1,2,5
c. Only 2,3,5
d. All of these