Q
What is the purpose of using block scope in JavaScript?

Answer & Solution

Answer: Option B
Solution:
Block scope in JavaScript is used to prevent variable hoisting and ensure variables are only accessible within the block they are defined in.
Related Questions on Average

What is the purpose of using the const keyword in JavaScript?

A). A. To declare variables with global scope

B). B. To declare block-scoped variables

C). C. To declare variables that can be reassigned

D). D. To declare variables that cannot be reassigned

Which of the following is NOT an example of a block in JavaScript?

A). A. Function body

B). B. if statement body

C). C. while loop body

D). D. Object literal

Which keyword is used to declare a constant array in JavaScript?

A). A. let

B). B. const

C). C. var

D). D. array

Which keyword is used to declare block-scoped variables in JavaScript?

A). A. var

B). B. let

C). C. const

D). D. block

What will be the output of the code above?

A). A. 10

B). B. 20

C). C. Error

D). D. Undefined

What will be logged to the console after 1 second?

A). A. 0 1 2

B). B. 3 3 3

C). C. 0 0 0

D). D. Error

What will be logged to the console?

A). A. 'Alice'

B). B. 'Bob'

C). C. TypeError

D). D. Undefined

What does the const keyword signify in JavaScript?

A). A. Constant variable

B). B. Mutable variable

C). C. Global variable

D). D. Block-scoped variable

What is the primary difference between const and let in JavaScript?

A). A. const variables can be reassigned

B). B. let variables are block-scoped

C). C. const variables are hoisted

D). D. let variables are immutable

What happens if you try to reassign a value to a constant declared using const?

A). A. SyntaxError

B). B. TypeError

C). C. ReferenceError

D). D. No error, value is reassigned