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: bird 
Words: hummingbird, tackle, crane, hoist, tackle

SOLUTION: tackle

PROBLEM: Category: secretary duty 
Words: correspondence, schedule, answer calls, keys, file

SOLUTION: keys

PROBLEM: Category: chocolate food 
Words: chocolate cake, fix, chocolate, fudge, heavy

SOLUTION:
fix