Given a category and a set of five words, find the word from the set that does not belong (i.e. is the least relevant) with the other words in the category. Words are separated by commas.

[Q]: Category: chocolate food 
Words: fudge, chocolate cake, pudding, unwarranted, heavy
[A]: unwarranted


[Q]: Category: consumer product 
Words: merchandise, happy, thing, content, service
[A]: happy


[Q]: Category: baby animals 
Words: hatchling, expression, fawn, kitten, cub
[A]:
expression