Whom to file GSTR 9C

My turnover for f. Y. 17-18 is less then 50 lac. My book of account did not come under audit as per income tax. As per my knowledge more than turnover of rs. 2 crore required to file GSTR9 C. When I get entered in annual return section on site its shows GSTR9 AND 9C Both visible to file.
Pls Advice me did I required to file both or only GSTR9.
THANKS IN ADVANCE.