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

MPT FIM GJN DGI

DGI

MPT⇒  M →(+3)→ P→(+4) →T FIM ⇒ F →(+3)→ I→(+4) →M GJN ⇒ G →(+3)→ J→(+4) →N DGI ⇒ D →(+3)→ G→(+2) →I(ODD)