Compare each letter's position number with its coded letter to find the shift: H(8)→F(6) is -2, O(15)→M(13) is -2, R(18)→P(16) is -2, S(19)→Q(17) is -2, E(5)→C(3) is -2. So every letter simply shifts back by 2 places. Apply this to MARE: M(13)→K(11), A(1)→ going back 2 from A wraps around to Y(25), R(18)→P(16), E(5)→C(3). Putting it together gives KYPC, option (4).