Four words have been given, out of which three are alike in some manner and one is different. Select the word that is different.

Equivocal Hesitant Ambivalent Certain

Certain

Equivocal - open to more than one interpretation Hesitant - not able to be relied Ambivalent - having mixed feelings or contradictory ideas about something or someone Certain - able to be firmly relied on to happen (odd)