Inheritance & Prototypes

Preview — 3 of 10 questions

What does the super keyword do in a subclass?

javascript

class Parent {
  constructor(name) {
    this.name = name;
  }
}

class Child extends Parent {
  constructor(name, age) {
    super(name);
    this.age = age;
  }
}

ACalls the parent class constructor

BCreates a new instance of the parent class

CRefers to the child class instance

DOverrides the parent class constructor

What happens when a subclass defines a method with the same name as a method in its parent class?

javascript

class Animal {
  speak() {
    return "Some sound";
  }
}

class Dog extends Animal {
  speak() {
    return "Woof";
  }
}

const dog = new Dog();
console.log(dog.speak()); // "Woof"

AJavaScript throws an error

BThe parent method is deleted

CThe subclass method overrides the parent method

DBoth methods are merged

Which statement about static methods is true?

javascript

class Example {
  static sayHello() {
    return "Hello!";
  }
}

AExample.sayHello() will work

Bnew Example().sayHello() will work

CStatic methods can access instance properties

DStatic methods are inherited automatically

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