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

WXYZ

WXYZ ⇒ In this letter cluster there is no any vowel (odd)

LMNO ⇒ In this letter cluster there is one any vowel

ABCD ⇒ In this letter cluster there is one any vowel

IJKL ⇒ In this letter cluster there is one any vowel