4. Show the Wrestler's Wedding Problem is NP-complete. Instance : A set W = {w1,w2 , , wn} of professional wrestlers, a collection of unordered pairs T = {(wi ,wj)lui, uy E W} where (ui, u'j) E T means that the wrestlers w, and w will attack each other if in the same room, and an integer K>0. Question Is there a wedding party of size K? (i.e., Is there a subset P C W such that if wi E P and wi E P then (wi, tuj) T.)