Fundamentals of Front End Development MCQs with Answers
Practice important Fundamentals of Front End Development MCQs with answers and explanations.
Chapter: 60
Q701:
What happens when the following code executes: <button onclick="getElementById('demo').innerHTML=Date()">?
A. The button text is updated to the current date
B. The content of the demo element is updated with the current date
C. The button triggers an alert with the date
D. The date is logged to the console
Correct Answer:
B
Chapter: 60
Q702:
Fill in the blank: JavaScript code can be executed automatically when a page is _____.
A. loaded
B. closed
C. printed
D. resized
Correct Answer:
A
Chapter: 60
Q703:
Which of the following will change the content of a div element with id="demo"?
A. document.getElementById('demo').innerHTML = "Hello"
B. document.getElementById('demo').text = "Hello"
C. document.getElementById('demo').value = "Hello"
D. document.getElementById('demo').content = "Hello"
Correct Answer:
A
Chapter: 60
Q704:
Fill in the blank: The JavaScript function Date() returns the ________.
A. current date and time
B. current time only
C. current month
D. current year
Correct Answer:
A
Chapter: 61
Q705:
What is a JavaScript string?
A. A type of number
B. A series of characters
C. A function definition
D. An HTML element
Correct Answer:
B
Chapter: 61
Q706:
Fill in the blank: A string in JavaScript can be enclosed in _________.
A. single quotes only
B. double quotes only
C. either single or double quotes
D. curly braces
Correct Answer:
C
Chapter: 61
Q707:
Which property is used to find the length of a string in JavaScript?
A. length
B. size
C. count
D. characters
Correct Answer:
A
Chapter: 61
Q708:
Fill in the blank: To avoid issues with quotes in a string, use the ________ character.
A. backslash
B. dollar sign
C. ampersand
D. colon
Correct Answer:
A
Chapter: 61
Q709:
What does the following code do: var y = "We are the so-called \"Vikings\" from the north."?
A. Includes double quotes in the string
B. Causes a syntax error
C. Converts the string to uppercase
D. Changes the string to a number
Correct Answer:
A
Chapter: 61
Q710:
How can you break a long JavaScript statement for better readability?
A. By using multiple backslashes
B. By breaking it after an operator
C. By adding extra semicolons
D. By inserting comments
Correct Answer:
B
Chapter: 61
Q711:
Fill in the blank: To concatenate strings in JavaScript, you use the ________ operator.
A. +
B. -
C. *
D. /
Correct Answer:
A
Chapter: 61
Q712:
How do you create a string object in JavaScript?
A. Using single quotes
B. Using the new String keyword
C. Using double quotes
D. Using the new Object keyword
Correct Answer:
B
Chapter: 61
Q713:
Fill in the blank: Primitive strings in JavaScript are treated as objects when ________.
A. assigned to a variable
B. passed to a function
C. methods or properties are executed
D. converted to numbers
Correct Answer:
C
Chapter: 61
Q714:
Which of the following correctly creates a string in JavaScript?
A. var str = "Hello World";
B. var str = new String("Hello World");
C. var str = 'Hello World';
D. All of the above
Correct Answer:
D
Chapter: 61
Q715:
Fill in the blank: To include a single quote inside a string enclosed in single quotes, use the ________ character.
A. double quote
B. backslash
C. single quote
D. dollar sign
Correct Answer:
B
Chapter: 62
Q716:
What is the default storage format for numbers in JavaScript?
A. 32-bit Integer
B. 64-bit Floating Point
C. 16-bit Floating Point
D. 64-bit Integer
Correct Answer:
B
Chapter: 62
Q717:
Fill in the blank: JavaScript numbers are stored as ________ precision floating point numbers.
A. single
B. double
C. triple
D. quadruple
Correct Answer:
B
Chapter: 62
Q718:
What does the 0xFF notation represent in JavaScript?
A. Decimal number
B. Hexadecimal number
C. Binary number
D. Octal number
Correct Answer:
B
Chapter: 62
Q719:
Fill in the blank: The value returned when dividing a number by zero in JavaScript is ________.
A. NaN
B. Infinity
D. undefined
Correct Answer:
B
Chapter: 62
Q720:
Fill in the blank: To check if a value is not a number, you can use the ________ function.
A. isNaN()
B. isNumber()
C. checkNumber()
D. isNotNumber()
Correct Answer:
A