which of the following is correct

The reciprocity effect states:
that individuals like others who like and/or positively evaluate them
that higher frequency of contacts and meetings amplifies the attraction between two people.
that an attraction is likely to develop when a person discovers that they have more in common with another person in terms of their shared attitudes, beliefs and preferences
that attractive people possess positive qualities beyond their physical appearance

All of the statements are correct regarding the reciprocity effect.