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 is the output of car.start() if var car = {start: function() {console.log('Car started');}};?
A). Car
B). started
C). Car started
D). Error
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
How can you check if a property exists in an object?
A). 'property' in object
B). object.hasProperty('property')
C). object.contains('property')
D). object.includes('property')
How do you define a method in a constructor function?
A). this.methodName = function() {}
B). this.methodName: function() {}
C). this.methodName = () {}
D). this.methodName: () {}
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 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 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
How do you define a method inside a class in JavaScript ES6?
A). methodName() {}
B). this.methodName = function() {}
C). function methodName() {}
D). methodName: function() {}