Is it really this hard, or I am thinking very critical ??!?

FEL + AI --> ALIFE
URS + AA --> AURAS
CERV + OE --> CORVEE
BOV + AE --> ABOVE
CAN + OE --> OCEAN
UECM + AI --> AECIUM

So, the above six, form meaningful English words when combined with 2 vowels and re-arranged.
But VULP + (any two vowels) --> No meaningful word.

So, VULP is odd one out !!

Priya, you should mention the sense in which it's "odd".