CodeParkfunction Animal(name) {
this.name = name;
}
Animal.prototype.speak = function () {
return this.name + " makes a sound";
};
const dog = new Animal("Rex");
dog.speak = () => "Woof";
delete dog.speak;
console.log(dog.speak(), Object.getPrototypeOf(dog) === Animal.prototype);
Rex makes a sound true
The answer is Rex makes a sound true. Assigning dog.speak created an own property that hid the prototype method. delete removes only that own property. So the lookup goes back to Animal.prototype.speak. Also, new links the instance to Animal.prototype, so the comparison is true.
The tempting option "TypeError: dog.speak is not a function" is wrong because delete does not touch the method on the prototype.