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 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
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 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 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 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 logged to the console?
A). A. 'John'
B). B. 'Jane'
C). C. Error
D). D. Undefined
What will be the output of the code above?
A). A. 10
B). B. 20
C). C. Error
D). D. Undefined
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
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