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

What will be logged to the console?

A). A. 'John'

B). B. 'Jane'

C). C. Error

D). D. Undefined

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. [1, 2, 3, 4]

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

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

D). D. Error

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

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 after 1 second?

A). A. 0 1 2

B). B. 3 3 3

C). C. 0 0 0

D). D. Error

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

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

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