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.

VDCKA

ADGPI ⇒ Ist and last letter is vowel in this letter - cluster

OMKLU  ⇒ Ist and last letter is vowel in this letter - cluster

VDCKA ⇒ only last letter is  not vowel in this letter - cluster (odd)

ECVMU ⇒ Ist and last letter is vowel in this letter - cluster