What is the primary advantage of using block scope in JavaScript?
A). Reducing code size
B). Preventing variable hoisting
C). Avoiding global variables
D). Improving performance
What will be the output of the code above?
A). 30
B). 31
C). TypeError
D). Undefined
What will be the output of the code above?
A). 10
B). 20
C). Error
D). Undefined
Which keyword is used to declare block-scoped variables in JavaScript?
A). var
B). let
C). const
D). block
How can you declare a constant named PI with a value of 3.14 in JavaScript using const?
A). const PI = 3.14;
B). PI = 3.14;
C). let PI = 3.14;
D). var PI = 3.14;
Which of the following statements is true about block scope in JavaScript?
A). Variables declared with let have global scope
B). Variables declared with let have function scope
C). Variables declared with let are block-scoped
D). Variables declared with let are hoisted
In JavaScript, const variables are not hoiste What does this mean?
A). They are hoisted to the top of the block
B). They cannot be used before declaration
C). They are accessible in nested scopes
D). They are block-scoped variables
What happens if you try to declare a const variable without initializing it immediately?
A). SyntaxError
B). ReferenceError
C). TypeError
D). No error, the variable remains undefined
Which statement about JavaScript's const is true?
A). const variables can be redeclared
B). const variables are globally scoped
C). const variables are mutable
D). const variables cannot be reassigned
What will be logged to the console after executing the code above?
A). ['red', 'blue', 'green', 'yellow']
B). ['red', 'blue', 'green']
C). ['yellow']
D). Error