How do you check if an object has a property "col...

How do you inherit properties and methods from a...

A). class SubClass extends SuperClas...

B). class SubClass inherits SuperCla...

C). class SubClass implements Super...

D). class SubClass derives SuperCla...

How do you define a constructor function for crea...

A). function Car(make, model) { thi...

B). Car(make, model) { this.make = m...

C). var Car = function(make, model) ...

D). Car = function(make, model) { t...

What is the output of console.log(obj.prop) if ob...

A). It prints undefined.

B). It throws an error.

C). It prints null.

D). It prints true.

What does the Object.values(obj) method return?

A). An array of object keys.

B). An array of object values.

C). An array of object properties.

D). An array of object methods.

What is the purpose of the 'this' keyword in a co...

A). It refers to the new object bei...

B). It refers to the global object.

C). It refers to the current object.

D). It refers to the parent object.

How can you remove a property 'email' from an obj...

A). delete user.email;

B). user.remove('email');

C). user.email = null;

D). user.pop('email');

What does Object.keys(obj) return?

A). An array of object keys.

B). An array of object values.

C). An array of object properties.

D). An array of object methods.

How do you add a new property 'age' with value 25...

A). person.age = 25;

B). person['age'] = 25;

C). person.add('age', 25);

D). person.push('age', 25);

How do you get the number of properties in an obj...

A). Object.keys(book).length

B). book.countProperties()

C). book.totalProperties()

D). book.length()

What will console.log(obj.toString()) output?

A). The string representation of...

B). The object itself.

C). An error.

D). 1