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

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

A). The string representation of...

B). The object itself.

C). An error.

D). 1

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);

What happens if you access a non-existent property...

A). It returns undefined.

B). It throws an error.

C). It returns null.

D). It returns true.

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()

How do you access a property called 'name' from an...

A). person.name

B). person['name']

C). person->name

D). person::name

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.

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.

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: () {}

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)