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.

Input: Consider Input: Category: physical property 
Words: fat, vitamin c, area, brittleness, absorption

Output: vitamin c


Input: Consider Input: Category: corporate 
Words: corporation, firm, synergy, tough, concerted

Output: tough


Input: Consider Input: Category: window material 
Words: lead, metal, glass, plate, wood


Output: plate