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 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()
What will console.log(newCar.make); output if class Car { constructor(make) { this.make = make; }} var newCar = new Car('Honda');?
A). Honda
B). Car
C). Undefined
D). Error
How do you create an instance of the Car object using the constructor function?
A). var myCar = new Car('Toyota', 'Corolla');
B). var myCar = Car('Toyota', 'Corolla');
C). var myCar = create Car('Toyota', 'Corolla');
D). var myCar = construct Car('Toyota', 'Corolla');
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 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 define a method inside a class in JavaScript ES6?
A). methodName() {}
B). this.methodName = function() {}
C). function methodName() {}
D). methodName: function() {}
What is the correct way to create an object in JavaScript?
A). var obj = {};
B). var obj = [];
C). var obj = ();
D). var obj = {};
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 is the output of console.log(person.greet()); if var person = {greet: function() {return 'Hello';}};?
A). Hello
B). Undefined
C). Error
D). Hello