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

PTZW MQWT FJPM TXDB

TXDB

PTZW  ⇒ P → (+4) → T → (+6) →Z → (-3) → W MQWT⇒  M → (+4) → Q → (+6) → W → (-3) → I FJPM  ⇒ F → (+4) →J → (+6) →P → (-3) → M TXDB ⇒ T → (+4) → X → (+6) → D → (-2) → D (ODD)