Select the letter-cluster that can replace the question mark(?) in the following series.

IHUW : HFRS :: LMQT : ?

KKNP

A   B   C    D   E    F   G    H    I    J    K    L   M

 ↓    ↓    ↓    ↓    ↓     ↓   ↓    ↓     ↓   ↓    ↓    ↓    ↓

 Z   Y    X   W   V    U   T    S    R   Q   P    O   N

26  25  24  23  22  21  20  19  18  17  16  15  14

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THE LOGIC FOLLOWED HERE IS :

I → (-1) → H

H → (-2) → F

U → (-3) → R

W → (-4) → S

SIMILARLY

L → (-1) → K

M → (-2) → K

Q → (-3) → N

T → (-4) → P