Explanation:

Let’s break it down with the pairs:

- First look: KTM ? PGN

- K to P: K is the 11th letter, P is the 16th. That’s a +5 shift.

- T to G: T is 20, G is 7. That’s a +13 shift, but since the alphabet wraps, 20+13=33, minus 26 letters = 7. So, +13.

- M to N: M is 13, N is 14. That’s +1.

- Now, ABC ? ?

- A +5 = F (A=1, 1+5=6, F)

- B +13 = O (B=2, 2+13=15, O)

- C +1 = D (C=3, 3+1=4, D)

But none of the options match “FOD.” So, maybe the pattern is different.

Let’s check letter order backwards (reverse):

- KTM ? PGN is not reversal.

- Let’s check letter symmetry:

- KTM: If we map each letter to its opposite (Z=1, Y=2…A=26)

- K(11) ? P(16)

- T(20) ? G(7)

- M(13) ? N(14)

- It looks like each pair adds up to 27 (K=11, P=16; 11+16=27)

- T=20, G=7; 20+7=27

- M=13, N=14; 13+14=27

That’s the thing! The trick is: Each pair's positions add up to 27.

So, for ABC:

- A: 1 ? 26 (Z: 26, 1+26=27)

- B: 2 ? 25 (Y: 25, 2+25=27)

- C: 3 ? 24 (X: 24, 3+24=27)

So, ABC should map to ZYX.

Now, options:

- 1: ZWY

- 2: ZYW

- 3: ZYX

- 4: ZXY

Clearly, option 3 (ZYX) is correct.