How do you add a new property to an existing object in JavaScript?
A). object.property = value;
B). object->property = value;
C). object:property = value;
D). object.addProperty('property', value);
Which of the following is a correct way to define an object using an object literal?
A). var car = {make: 'Toyota', model: 'Corolla'};
B). var car = make: 'Toyota', model: 'Corolla';
C). var car = new Object(make: 'Toyota', model: 'Corolla');
D). var car = Object.create(make: 'Toyota', model: 'Corolla');
How do you create a method inside an object using an object literal?
A). methodName: function() {}
B). methodName = function() {}
C). methodName: () {}
D). methodName: method() {}
Which of the following correctly creates an instance of a Car object using a constructor function?
A). var myCar = Car('Toyota', 'Corolla', 2020);
B). var myCar = new Car('Toyota', 'Corolla', 2020);
C). var myCar = create Car('Toyota', 'Corolla', 2020);
D). var myCar = construct Car('Toyota', 'Corolla', 2020);
What will car['make'] return if var car = {make: 'Ford', model: 'Mustang'};?
A). Ford
B). Mustang
C). Undefined
D). Error
What is encapsulation in the context of JavaScript objects?
A). Hiding the internal state and requiring all interaction to be performed through an object's methods
B). Extending one object from another
C). Creating a new object
D). Removing a property from an object
What does Object.keys(obj) return?
A). An array of the values of the object's properties
B). An array of the names of the object's properties
C). The first key of the object
D). The number of properties in the object
Which method can be used to call a function defined within an object?
A). object.functionName();
B). object->functionName();
C). object::functionName();
D). object.callFunction('functionName');
What is the output of car.start() if var car = {start: function() {console.log('Car started');}};?
A). Car
B). started
C). Car started
D). Error
How can you iterate over all properties of an object?
A). for (var key of object)
B). for (var key in object)
C). for (var key with object)
D). for (var key over object)