Find Youngest Person

/* Write a JavaScript function findYoungestPerson(persons) that accepts as parameter an array of persons,
finds the youngest person and returns his full name. Write a JS program youngestPerson.js to execute your function
for the below examples and print the result at the console. */

"use strict";

function findYoungestPerson(persons) {
    persons.sort(function(a, b) {
        return a.age - b.age;
    });

    return 'The youngest person is ' + persons[0].firstname +
        ' ' + persons[0].lastname;
}

var persons = [
    { firstname: 'George', lastname: 'Kolev', age: 32},
    { firstname: 'Bay', lastname: 'Ivan', age: 81},
    { firstname: 'Baba', lastname: 'Ginka', age: 40}];

console.log(findYoungestPerson(persons));