In the following question, which one set of letters when sequentially placed at the gaps in the given letter series shall complete it? I _ P _ RI _ P _ R _ T _ VR _ _ _ V

R T V T V I P I T P P T T V V I P I T P R T T V V I P I I P P T I P I V V T T R

R T V T V I P I T P

R I T P V R I T P V R I T P V R I T P V