Select the option that is related to the third letter-cluster in the same way as the second letter-cluster is related to the first letter-cluster.

PURPLE : OWOTGK :: GREEN : ?

FTBII

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 :

P → (-1) → O

U → (+2) → W

R → (-3) → O

P → (+4) → T

L → (-5) → G

E → (+6) → K

SIMILARLY

G → (-1) → F

R → (+2) → T

E → (-3) → B

E → (+4) → I

N → (-5) → I