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 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 define a class in JavaScript ES6?
A). class ClassName { constructor() {} }
B). function ClassName() { constructor() {} }
C). class ClassName() { constructor {} }
D). function class ClassName { constructor() {} }
How do you inherit properties and methods from another class in JavaScript ES6?
A). class SubClass extends SuperClass {}
B). class SubClass inherits SuperClass {}
C). class SubClass implements SuperClass {}
D). class SubClass super SuperClass {}
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 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;
What will console.log(car.make); output if var car = {make: 'Toyota', model: 'Corolla'};?
A). Toyota
B). Corolla
C). Undefined
D). Error
What will the following code output? console.log(person['age']); if var person = {name: 'John'};
A). 30
B). John
C). undefined
D). null
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 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