What does Object.keys(obj) return?

What does Object.assign(target, ...sources) do?

A). Copies properties from sources to target

B). Compares properties between target and sources

C). Deletes properties in sources

D). Merges properties of sources into target and removes duplicates

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)

What will car['make'] return if var car = {make: 'Ford', model: 'Mustang'};?

A). Ford

B). Mustang

C). Undefined

D). Error

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 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 is the correct way to delete a property from an object?

A). remove object.property;

B). delete object.property;

C). delete object[property];

D). object.property = null;

How do you define a method in a constructor function?

A). this.methodName = function() {}

B). this.methodName: function() {}

C). this.methodName = () {}

D). this.methodName: () {}

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 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

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')