What will the following code output? console.log(person['age']); if var person = {name: 'John'};

How can you check if the age property exists in the person object?

A). 'age' in person

B). person.has('age')

C). person.contains('age')

D). person.hasOwnProperty('age')

What is the correct way to create an object in JavaScript?

A). var obj = {};

B). var obj = [];

C). var obj = ();

D). var obj = <>;

How do you call a method from a parent class in a subclass in JavaScript ES6?

A). super.methodName()

B). this.methodName()

C). parent.methodName()

D). base.methodName()

How do you add a method to an object created with a constructor function?

A). this.methodName = function() {}

B). this.methodName: function() {}

C). this.methodName = () {}

D). this.methodName: () {}

How do you iterate over all properties of an object var person = {name: 'John', age: 30};?

A). for (var key in person)

B). for (var key of person)

C). forEach(key in person)

D). forEach(key of person)

What does Object.keys(person) return if var person = {name: 'John', age: 30};?

A). ['name', 'age']

B). ['John', 30]

C). {'name', 'age'}

D). {'John', 30}

How do you define a method inside a class in JavaScript ES6?

A). methodName() {}

B). this.methodName = function() {}

C). function methodName() {}

D). methodName: function() {}

How do you define a method named greet in an object var person = {};?

A). person.greet = function() {};

B). person.greet: function() {};

C). person.greet = () {};

D). person.greet = function {};

What will console.log(car.make); output if var car = {make: 'Toyota', model: 'Corolla'};?

A). Toyota

B). Corolla

C). Undefined

D). Error

How do you add a new property gender with value male to the person object?

A). person.gender = 'male';

B). person.gender = male;

C). person.gender = ['male'];

D). person[gender] = 'male';