The term used to denote a group of families in the vedic society was

Answer: Option C

The Kula i.e. the family was the basis of both social and political organisations. Unit of Kula (the family) is headed by Kulapa.
The Grama was above the Kula. A group of Kula (families) formed a Grama (the village). Unit of Grama (the village) is headed by Gramani.
The Vis was above the Grama. A group of Grama formed a Vis. Unit of Vis (the clan) is headed by Vispati.
The Jana was above the Vis . A group of Vis formed a Jana. Unit of Jana (the people) is headed by Gopa or Gopati.
The Rashtra was above the Jana . A group of Jana formed a Rashtra. Unit of Rashtra (the country) is headed by Rajan.