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

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

A). The string representation of...

B). The object itself.

C). An error.

D). 1

How do you iterate over all properties of an obj...

A). for (var prop in person)

B). forEach(prop in person)

C). for (var prop of person)

D). forEach(prop of person)

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 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.

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 do you add a method to an object created wit...

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

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

C). this.methodName = () {}

D). this.methodName: () {}

What is the purpose of the 'super' keyword in a ...

A). It calls methods from the paren...

B). It creates a new instance of the...

C). It refers to the current object.

D). It checks for property existence.

How do you access nested properties in an object?

A). obj.property.nestedProp (B21)

B). obj['property']['nestedProp'] (C21)

C). obj.property['nestedProp'] (D21)

D). obj['property'].nestedProp (E21)