Fundamentals of Front End Development MCQs with Answers
Practice important Fundamentals of Front End Development MCQs with answers and explanations.
Chapter: 68
Q781:
What does the statement var points = [40, 100, 1, 5, 25, 10]; do?
A. Creates a new array with six elements
B. Creates an empty array
C. Initializes a new object
D. Creates an array with undefined elements
Correct Answer:
A
Chapter: 68
Q782:
Fill in the blank: JavaScript arrays are best described as ________.
A. Objects
B. Strings
C. Numbers
D. Functions
Correct Answer:
A
Chapter: 68
Q783:
What will person[1] return if person = ["Adil", "Anwar", 46];?
A. "Anwar"
B. 46
C. "Adil"
D. Undefined
Correct Answer:
A
Chapter: 68
Q784:
Fill in the blank: To avoid complications in code, it is recommended to use ________ instead of new Array().
A. []
B. {}
C. new Array()
D. Array()
Correct Answer:
A
Chapter: 68
Q785:
What will typeof fruits return if fruits is defined as var fruits = ["Banana", "Orange", "Apple", "Mango"];?
A. "object"
B. "array"
C. "string"
D. "array object"
Correct Answer:
A
Chapter: 68
Q786:
Fill in the blank: JavaScript arrays should use ________ for better clarity and to avoid side effects.
A. Array literals
B. Constructor function
C. Object properties
D. String literals
Correct Answer:
A
Chapter: 69
Q787:
What does the valueOf() method return for an array?
A. Array as a string
B. Array as an object
C. Array as a comma-separated string
D. Array as a JSON object
Correct Answer:
C
Chapter: 69
Q788:
What does the pop() method do to an array?
A. Adds a new element at the end
B. Removes the last element
C. Removes the first element
D. Adds a new element at the beginning
Correct Answer:
B
Chapter: 69
Q789:
What does the shift() method do to an array?
A. Removes the last element
B. Adds a new element at the end
C. Removes the first element
D. Reverses the order of elements
Correct Answer:
C
Chapter: 69
Q790:
Fill in the blank: The splice() method can be used to ________.
A. Add new items to an array
B. Remove elements from an array
C. Both add new items and remove elements
D. Reverse the elements in an array
Correct Answer:
C
Chapter: 69
Q791:
What will be the result of fruits.sort() if fruits is ["Banana", "Orange", "Apple", "Mango"]?
A. ["Apple", "Banana", "Mango", "Orange"]
B. ["Banana", "Apple", "Orange", "Mango"]
C. ["Apple", "Banana", "Orange", "Mango"]
D. ["Mango", "Orange", "Banana", "Apple"]
Correct Answer:
A
Chapter: 69
Q792:
Fill in the blank: The reverse() method ________.
A. Sorts the elements in ascending order
B. Sorts the elements in descending order
C. Reverses the order of the elements
D. Adds new elements to the array
Correct Answer:
C
Chapter: 69
Q793:
What will the array fruits be after fruits.splice(2, 1, "Lemon", "Kiwi") if fruits is ["Banana", "Orange", "Apple", "Mango"]?
A. ["Banana", "Orange", "Lemon", "Kiwi", "Mango"]
B. ["Banana", "Orange", "Kiwi", "Mango"]
C. ["Banana", "Orange", "Apple", "Lemon", "Kiwi", "Mango"]
D. ["Banana", "Lemon", "Kiwi", "Mango"]
Correct Answer:
A
Chapter: 69
Q794:
Fill in the blank: The length property of an array returns the ________.
A. Number of elements in the array
B. Index of the last element
C. Array as a string
D. Number of characters in the array
Correct Answer:
A
Chapter: 69
Q795:
What will fruits[fruits.length] do if fruits is ["Banana", "Orange", "Apple", "Mango"]?
A. Add a new element at the end
B. Remove the last element
C. Access the last element
D. Return an undefined element
Correct Answer:
A
Chapter: 69
Q796:
Fill in the blank: To remove the first element from an array, you should use the ________ method.
A. shift
B. pop
C. splice
D. reverse
Correct Answer:
A
Chapter: 69
Q797:
What does the toString() method return for an array?
A. Array as a comma-separated string
B. Array as an object
C. Array as a JSON object
D. Array as a string
Correct Answer:
A
Chapter: 69
Q798:
Fill in the blank: The push() method adds elements to the ________ of the array.
A. End
B. Beginning
C. Middle
D. Random
Correct Answer:
A
Chapter: 70
Q799:
What does the sort() function use to determine the order of elements?
A. A random function
B. A compare function
C. The array length
D. The array index
Correct Answer:
B
Chapter: 70
Q800:
What is the purpose of a compare function in sorting arrays?
A. To filter out elements
B. To define an alternative sort order
C. To add elements to the array
D. To remove elements from the array
Correct Answer:
B