javascript quiz question

quiz.js

function House() {
  this.vandalize = function() {
    this.vandalized = true;
  }
}

function Punk() {
  this.onParty = function(handler) {
    this.handler = handler;
  }

  this.party = function() {
    this.handler();
  }
}

house = new House();
punk = new Punk();
punk.onParty(house.vandalize);
punk.party();

console.log(punk.vandalized);
console.log(house.vandalized);