Which of these is an incorrect form of using method max()

Which of these is an incorrect form of using method max() to obtain a maximum element?

1. max(List c)
2. max(Comparator comp)
3. max(Collection c)
4. max(Collection c, Comparator comp)
5. None of these

Its illegal to call max() only with comparator, we need to give the collection to be searched into.