JavaScript Multiple-Choice Questions
for online exam

JavaScript is currently one of the most popular programming languages, and it is essentially a web language. This is mainly used to develop web development and back-end development. JavaScript is a language and development server commonly used on clients. JavaScript provides an extensive standard library of various functions and methods available to support development processes, making it easy and lighter the entire process.

MCQs on JavaScript Language

Solve JavaScript Multiple-Choice Questions to prepare better for GATE. If you wish to learn more about JavaScript language and JavaScript MCQs, you can check notes, mock tests, and previous years’ question papers. Gauge the pattern of MCQs on JavaScript by solving the ones that we have compiled below for your practice:

JavaScript Multiple-Choice Questions

1. The ” var” and “function” are known as _____________.

a. Data types

b. Keywords

c. Prototypes

d. Declaration statements

Answer: (d) Declaration statements

2. Which of these is the correct way in which we can call the JavaScript code?

a. Triggering Event

b. Preprocessor

c. Function/Method

d. RMI

Answer: (c) Function/Method

3. Which of these functions of the Number Object would format a number with different numbers of digits to the decimal’s right?

a. toFixed()

b. toExponential()

c. toLocaleString()

d. toPrecision()

Answer: (a) toFixed()

4. Out of the following functions of the string object, which one would return the character in any string via the specified number of characters starting at a specified position?

a. search()

b. substr()

c. split()

d. slice()

Answer: (b) substr()

5. Look at the snippets given below and check the one in which the variable “a” isn’t equal to the “NULL”.

a. if (a!)

b. if(a!=null)

c. if(a!==null)

d. if(a!null)

Answer: (c) if(a!==null)

6. In JavaScript, what do we use for calling the expression for function definition?

a. Function literal

b. Function prototype

c. Function declaration

d. Function calling

Answer: (a) Function literal

7. Which of these is used in JavaScript for calling a method or a function?

a. Functional Expression

b. Property Access Expression

c. Primary Expression

d. Invocation Expression

Answer: (d) Invocation Expression

8. Which of these operators are used for checking if a specific property exists?

a. in

b. within

c. exist

d. exists

Answer: (a) in

9. “The expression that can appear legally on an assignment expression’s left side” is a common explanation for variables, elements of arrays, and properties of objects. These are known as __________:

a. Prototypes

b. Properties

c. Lvalue

d. Definition

Answer: (c) Lvalue

10. Which of these is a correct output for the JavaScript code given below?

string X= “Hey”;

string Y=”There”;


a. Hey There

b. Hey_There

c. HeyThere

d. undefined

Answer: (c) HeyThere

11. Which of these is known as the Equality operator used for checking whether both the values are equal?

a. =

b. ==

c. ===

d. &&

Answer: (b) ==

12. In case a value of an operator is NULL, then the unary operator would return the ____________ typeof.

a. object

b. boolean

c. string

d. undefined

Answer: (d) undefined

13. Which of these is not a keyword?

a. debugger

b. use strict

c. with

d. if

Answer: (b) use strict

14. Which of these symbols is used to create comments in JavaScript?

a. //

b. \\

c. \* */

d. \* *\

Answer: (a) //

15. In the line of code given below, what will the “datatype” written in brackets be called?


a. An object

b. A String

c. Floating point

d. An integer

Answer: (b) A String

16. In the line of code given below, the prototype represents the _____________.


a. Prototype of a function

b. Function x

c. Not valid

d. A custom constructor

Answer: (a) Prototype of a function

17. Which of these methods or operators are used for identifying an array?

a. isarrayType()

b. ===

c. ==

d. Typeof

Answer: (a) isarrayType()

18. A function’s execution would stop whenever a program control would encounter the _________ statement in the function’s body.

a. goto statement

b. break statement

c. continue statement

d. return statement

Answer: (d) return statement

19. Which of these codes is equivalent to the code given below?


a. a [ “x” ] ( g , h );

b. x (g) &&a.x (h);

c. x( g&&h );

d. a (x )[ “g” , “h” ];

Answer: (a) a [ “x” ] ( g , h );

20. Which of these keywords is used to define various functions in JavaScript?

a. function

b. main

c. init

d. Void

Answer: (a) function

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