Question: To which predicted relation class does the self-relation of the object sample in image no.5 belong?
SQL: SELECT T1.PRED_CLASS FROM PRED_CLASSES AS T1 INNER JOIN IMG_REL AS T2 ON T1.PRED_CLASS_ID = T2.PRED_CLASS_ID WHERE T2.IMG_ID = 5 AND T2.OBJ1_SAMPLE_ID = T2.OBJ2_SAMPLE_ID