In NKM, YVX, FCE, JGI: each triplet follows the pattern (X, X+3, X-3) in alphabetical position. For N(14)-K(11)-M(13): N→K is -3, K→M is +2 (not +3). Wait, let me re-examine. Actually N(14) to K(11) is -3, K(11) to M(13) is +2. ZAX: Z(26) to A(1) wraps around, not following the consistent positional pattern like the others. The correct answer is ZAX because it breaks the consistent -3,+2 or similar pattern.