6) The first four ionization energies of atoms of elements X, Y and Z are given below (where M = X, Y,Z):
ELEMENT M FIRST SECOND THIRD FOURTH
X 738 1450 7730 10550
Y 800 2427 3658 25024
Z 495 4563 6912 9540
Which element/s M is/are most likely to have a nitride compound with formula MN?
D. Both X and Y
E. Both Y and Z