How do you inherit properties and methods from another class in JavaScript ES6?

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';

How do you define a class in JavaScript ES6?

A). class ClassName { constructor() {} }

B). function ClassName() { constructor() {} }

C). class ClassName() { constructor {} }

D). function class ClassName { constructor() {} }

How can you delete the age property from the person object?

A). delete person.age;

B). remove person.age;

C). person.age = null;

D). person.age.delete;

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)

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 output of console.log(person.greet()); if var person = {greet: function() {return 'Hello';}};?

A). Hello

B). Undefined

C). Error

D). Hello

How do you access the value of the name property in the object var person = {name: 'John', age: 30};?

A). person['name']

B). person.name

C). person->name

D). person::name

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

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

B). ['John', 30]

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

D). {'John', 30}

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

A). 30

B). John

C). undefined

D). null