Four letter-clusters have been given in the options, out of which three are alike in some manner and one is different. Select the letter-cluster that is different.

ORVA EHLQ ILPU KOSW

KOSW

THE LOGIC; 1) ORVA, O → (+3) → R → (+4) → V → (+5) → A 2) EHLQ, E → (+3) → H → (+4) → L → (+5) → Q 3) ILPU, I → (+3) → L → (+4) → P → (+5) → U 4) KOSW, K → (+4) → O → (+4) → S → (+4) → W Thus, KOSW is the odd one.