What will be the output of the code above?
A). A. 30
B). B. 31
C). C. Error
D). D. Undefined
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
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 keyword is used to declare block-scoped variables in JavaScript?
A). A. var
B). B. let
C). C. const
D). D. block
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
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;
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 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
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