What will the following code output? console.log(person['age']); if var person = {name: 'John'};
A). 30
B). John
C). undefined
D). null
What is the purpose of the this keyword in a constructor function?
A). It refers to the new object being created.
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 with a constructor function?
A). this.methodName = function() {}
B). this.methodName: function() {}
C). this.methodName = () {}
D). this.methodName: () {}
What is the correct way to create an object in JavaScript?
A). var obj = {};
B). var obj = [];
C). var obj = ();
D). var obj = <>;
How do you define a constructor function for creating Car objects?
A). function Car(make, model) { this.make = make; this.model = model; }
B). Car(make, model) { this.make = make; this.model = model; }
C). var Car = function(make, model) { this.make = make; this.model = model; };
D). Car = function(make, model) { this.make = make; this.model = model; };
What does Object.keys(person) return if var person = {name: 'John', age: 30};?
A). ['name', 'age']
B). ['John', 30]
C). {'name', 'age'}
D). {'John', 30}
How can you delete the age property from the person object?
A). delete person.age;
B). remove person.age;
C). person.age = null;
D). person.age.delete;
How do you access the value of the name property in the object var person = {name: 'John', age: 30};?
A). person['name']
B). person.name
C). person->name
D). person::name
How do you add a new property gender with value male to the person object?
A). person.gender = 'male';
B). person.gender = male;
C). person.gender = ['male'];
D). person[gender] = 'male';
How do you define a method inside a class in JavaScript ES6?
A). methodName() {}
B). this.methodName = function() {}
C). function methodName() {}
D). methodName: function() {}