I know it’s A, B, and E For A you divide 24 by 3 For B you divide 56 by 7 And those both give 8 For C you divide 17 by 9 which isn’t 8. For D I think you’d subtract 13 from 21 which is 8 but then the equation is -x = 8 so to change x i think then it’d be x = -8 so I don’t think D is right but i’m not 100% sure