TASK DEFINITION: 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.
PROBLEM: Category: animal 
Words: trap, dog, fish, tiger, horse

SOLUTION: trap

PROBLEM: Category: animal 
Words: train, fly, jump, leap, grasshopper

SOLUTION: train

PROBLEM: Category: bird 
Words: duck, crane, dump truck, hoist, flamingo

SOLUTION:
dump truck