Coalition of Information Technology Business

Question 16

Coalition of Information Technology Business. Which JavaScript function is used to convert a string into an integer?

toInt()
convertInt()
parseInt()
stringToInt()

Question 17

In JavaScript, what does NaN stand for?

Not a Null
Not a Number
Negative and Null
None and Null

Question 18

Which of the following is the correct JavaScript statement to display text on a webpage?

response.write(“Hello how are you?”)
“Hello how are you?”
document.write(“Hello how are you?”)
(“Hello how are you?”)

Question 19

What happens if you define a function incorrectly in JavaScript (e.g., missing parentheses or using invalid syntax)?

✅ It will result in a syntax error
The function will continue to execute
It will result in no syntax errors
All of the above

Question 20

Which type of loop is NOT a standard loop structure in JavaScript?

for loop
✅ repeat loop
while loop
do…while loop

Question 21

Which method is used in JavaScript to access an HTML element by its ID?

Use the document.putElementById(id) method
✅ Use the document.getElementById(id) method
Use the document.retrieveElementById(id) method
Use the document.accessElementById(id) method

Question 22

Which of the following is the correct way to link an external JavaScript file in HTML?

✅ <script src=”main.js”>
<script href=”main.js”>
<script name=”main.js”>
<script value=”main.js”>

Question 23

Which of the following is the correct definition of a boolean?

✅ A logical data type which makes decisions. It supports only two possible values true or false
A logical data type which makes functions. It supports only one possible value const boolean = () => {}
A data type used to store functions, and arrays using scientific notation
A whole number without a decimal point

Question 24

Which of the following is the correct when to use floating-point numbers in JavaScript?

A data type used to store functions, and arrays using scientific notation
A whole number without a decimal point
A general data type used to store integers, floating-point numbers (decimals), and numbers using scientific notation
✅ Used whenever you’re working with data that requires numbers with a fractional component

Question 26

Which loop in JavaScript always executes the code block at least once before checking the condition?

for
while
✅ do…while
forEach

Question 27

Which option best describes null in JavaScript?

✅ Null refers to something with no value and explicitly set as null with code
Null refers to something with a value of void and explicitly set as void with code
Null refers to something with a value of undefined
Null refers to something with a value of 0

Question 28

Which is the correct way to declare an object person with properties name and age in JavaScript?

✅ let person = { name: “John”, age: 30 };
let person = (name: “John”, age: 30);
let person = “name”: “John”, “age”: 30;
let person = [“name”: “John”, “age”: 30];

Question 29

Which of the following is NOT a valid way to declare a variable in JavaScript?

let a = 10;
var a = 20;
✅ int a = 30;
const a = 40;

Question 30

Which of the following is the correct definition of BigInt in JavaScript?

✅ Type that represents integers that are too large for the standard Number type and has no limit
Type that has a maximum value of $2^{53} – 1$, which is about 9 quadrillion
Type that has a maximum value of $5^{06} – 1$, which is about 18 quadrillion
Type that represents integers that are too small for the standard Number type and has no limit

Question 31

Which of the following is a valid way to declare a variable and assign it the value of 10 in JavaScript?

variable x = 10;
✅ var x = 10;
let x := 10;
declare x = 10;

Question 34

Which keyword in JavaScript is used to declare a variable whose value cannot be reassigned after initialization?

var
let
✅ const
Set

Question 36

Which expression is the safest way to check if a variable is truly undefined, even if it hasn’t been declared?

myVar == undefined
✅ typeof myVar === ‘undefined’
myVar === undefined
isUndefined(myVar)

Question 37

Which of the following is true about the Object.assign() method in JavaScript?

It copies the values of all properties from one or more source objects to a target object.
It merges two or more objects into a new object.
It creates a shallow copy of an object.
✅ All of the above

Question 38

What does the JavaScript slice() method do when used on an array?

Removes the last element of an array.
✅ Extracts a portion of an array into a new array.
Splits an array into smaller arrays.
Combines two arrays into one.

Question 39

Which of the following is a correct way to add or update a property on a JavaScript object using dot notation?

object{property} = value
object.addProperty(“property”, value)
✅ object.property = value
object[“property”] = value

Question 40

Which of the following is a correct way to list the property names of a JavaScript object?

Object.values()
✅ Object.keys()
Object.entries()
Object.getOwnPropertyNames()

Question 41

Which array method combines all elements of an array into a single string, separated by a specified delimiter?

✅ join()
concat()
split()
toString()

Question 42

Which statement correctly describes how to add an element to the end of an array in JavaScript?

Use the array.pop() method
✅ Use the array.push() method
Use the array.shift() method
Use the array.unshift() method

Question 47

Which loop is used to iterate over iterable objects (like arrays, strings, maps, etc.) in JavaScript?

for…of ✅
for…in
while
do…while

Question 48

Which JavaScript operator is used for string concatenation?

/
+ ✅

Question 49

Which data type can be used to group related data and functionality together in JavaScript?

object ✅
null
undefined
String

Question 50

Which JavaScript operator is used as the conditional (ternary) operator?

===
? ✅
:
!!

Question 51

What does the JavaScript method Array.isArray() do?

Checks if an array is empty.
Checks if a variable is an array. ✅
Concatenates two arrays.
Removes duplicates from an array.

Question 52

Which HTML tag is used to embed or reference JavaScript code in a web page?

<javascript>
<js>
<script> ✅
<scripting>

Question 53

Which ECMAScript version introduced arrow functions like () => {}?

ECMAScript ES5
ECMAScript ES8
ECMAScript ES7
ECMAScript ES6 ✅

Question 54

Which of the following is the correct way to define a function named greet in JavaScript?

function greet(name) { console.log(“Hello ” + name); } ✅
def greet(name) { console.log(“Hello ” + name); }
function greet name { console.log(“Hello ” + name); }
function = greet(name) { console.log(“Hello ” + name); }

Question 59

What happens when you try to access a property that doesn’t exist on a JavaScript object?

JavaScript throws an error
It returns undefined
It returns null
It creates the property automatically

Question 64

Which JavaScript operator checks for equality without performing type coercion (strict equality)?

===
==
=
!=

Question 65

Which method is used to add one or more elements to the end of an array in JavaScript?

append()
✅ push()
add()
attach()

Question 66

Which of the following best describes the general JavaScript Number data type?

✅ A general data type used to store integers, floating-point numbers (decimals), and numbers using scientific notation
A whole number without a decimal point
Used whenever you’re working with data that requires numbers with a fractional component
A data type used to store functions, and arrays using scientific notation

Question 67

Which array method applies a function against an accumulator and each element in the array (from left to right) to reduce it to a single value? Coalition of Information Technology Business

✅ reduce()
forEach()
map()
filter()

Question 68

What does the JavaScript function parseFloat() do?

Parses a string and returns an integer.
Rounds a number to the nearest integer.
Converts a number to a string.
✅ Parses a string and returns a floating-point number.

Question 75

Which statement correctly describes block-scoped variables in JavaScript?

[✔] Block-scoped variables are only accessible inside the block in which they are defined.
Block-scoped variables are accessible anywhere in the function.
Block-scoped variables are accessible anywhere in the entire program.
Block-scoped variables are inaccessible once the block is finished.

Question 76

Which of the following is the correct syntax for accessing the value of a property in a JavaScript object using bracket notation?

object{key}
object.key
[✔] object[“key”]
object.key()

Question 77

Which of the following is the most common and straightforward way to declare an array with numbers 1, 2, and 3 in JavaScript?

[✔] let arr = [1, 2, 3];
let arr = new Array(1, 2, 3);
let arr = Array(1, 2, 3);
let arr = [1, “2”, 3];

Question 78

Which JavaScript array method removes the last element from an array?

removeLast()
deleteLast()
[✔] pop()
splice()

Question 79

Which operator in JavaScript checks if two values are NOT equal both in value and type?

!=
[✔] !==
==
===

Question 80

Which of the following statement is correct?

JavaScript is a High-Level Procedulary-Oriented, Multi-Paradigm Programming Language
JavaScript is a Low-Level Procedulary-Oriented, Single-Paradigm Programming Language
[✔] JavaScript is a High-Level Object-Oriented, Multi-Paradigm Programming Language
JavaScript is a Low-Level Object-Oriented, Multi-Paradigm Programming Language

Question 81

Which of the following are valid ways to access the age property of a JavaScript object named person?

person.get(‘age’)
[✔] person.age
person.getProperty(‘age’)
person[age]

Question 82

Which of the following is the single-line comment symbol in JavaScript?

[✔] //
/* */

Question 83

Which array method is used to merge two or more arrays without modifying the original arrays?

[✔] concat()
join()
slice()
push()

Question 84

Which statement correctly explains the difference between parameters and arguments in programming?

[✔] Parameters are used in the function definition, while arguments are the values that are passed into the function parameters when it is called
Parameters are values passed to a function, while Arguments are placeholders within the function
Parameters refer to data types, while Arguments represent the functions name
Parameters are used for conditional statements, while Arguments are utilized for loops within a function

Question 86

Which option best describes an integer in programming, specifically in JavaScript?

A data type used to store functions, and arrays using scientific notation
Used whenever you’re working with data that requires numbers with a fractional component
[✔] A whole number without a decimal point
A general data type used to store integers, floating-point numbers (decimals), and numbers using scientific notation

Question 87

Which of the following is a primitive data type used to represent a logical truth value in JavaScript?

[✔] true
false
undefined
null

Question 88

What does the break statement do inside a loop in JavaScript?

[✔] Exits the loop and stops the code inside it from executing.
Pauses the loop for a specified period of time.
Skips the current iteration and continues with the next one.
It causes an error in the loop. Coalition of Information Technology Business

Coalition of Information Technology Business

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