Which of the following is meaningful?

Which of the following are meaningful ?

Which of the following is not meaningful ?

Which of the following is not meaningful ?

Which of the following is not meaningful ?

Which of the following is not meaningful?

Which of the following is not meaningful? XIV (b) XXXV (c) XXV (d) VX

Which of the following is not meaningful? XXIII (b) XII (c) XVV (d) XIV

Which of the following is not meaningful? (a) XXIII (b) XII (c) XVV (d) XIV

Which of the following is not meaningful? (a) XIV (b) XXXV (c) XXV (d) VX

Let y=A sin (omegat-kx) represent the variation of distance y of a particle with time t. Which of the following is not meaningful?