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

Answer & Solution

Answer: Option C
Solution:
Block scope in JavaScript primarily helps in avoiding global variables, reducing the risk of variable naming conflicts and unintentional changes to global state.
Related Questions on Average

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 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 the output of the code above?

A). A. [1, 2, 3, 4]

B). B. [1, 2, 3]

C). C. [1, 2, 3, 4, 5]

D). D. Error

Which of the following statements is true about block scope in JavaScript?

A). A. Variables declared with let have global scope

B). B. Variables declared with let have function scope

C). C. Variables declared with let are block-scoped

D). D. Variables declared with let are hoisted

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

What will be the output of the code above?

A). A. 10

B). B. 20

C). C. Error

D). D. Undefined

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 purpose of using block scope in JavaScript?

A). A. To declare constants

B). B. To prevent variable hoisting

C). C. To improve code performance

D). D. To create global variables

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;

What will be logged to the console?

A). A. 'John'

B). B. 'Jane'

C). C. Error

D). D. Undefined