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

Answer & Solution

Answer: Option B
Solution:
The primary difference is that const variables are block-scoped, meaning they are only accessible within the block they are defined in, while let variables are mutable.
Related Questions on Average

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

What is the primary advantage of using block scope in JavaScript?

A). A. Reducing code size

B). B. Preventing variable hoisting

C). C. Avoiding global variables

D). D. Improving performance

Which of the following statements about const is true?

A). A. Variables declared with const can be reassigned

B). B. const variables have function scope

C). C. const variables cannot be used in loops

D). D. const variables are block-scoped

Which statement is true regarding the const keyword in JavaScript?

A). A. Constants declared with const are hoisted

B). B. Constants declared with const can be reassigned

C). C. Constants declared with const have global scope

D). D. Constants declared with const are immutable

What will be the output of the code above?

A). A. 10

B). B. 20

C). C. Error

D). D. Undefined

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

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

Which of the following statements is true about constants declared using const?

A). A. They can be reassigned multiple times

B). B. They are hoisted to the top

C). C. They are mutable

D). D. They are immutable

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

How can you declare a constant named PI with a value of 3.14 in JavaScript using const?

A). A. const PI = 3.14;

B). B. PI = 3.14;

C). C. let PI = 3.14;

D). D. var PI = 3.14;