What is the main difference between var and let in terms of scope?
A). var is block-scoped, let is function-scoped
B). var is function-scoped, let is block-scoped
C). Both var and let are block-scoped
D). Both var and let are function-scoped
How does block scope affect the visibility of variables in nested blocks?
A). Variables are only visible within their immediate block
B). Variables are visible within all nested blocks
C). Variables are only visible within functions
D). Variables are globally visible
What happens when you declare a constant with const inside a block and try to reassign it?
A). It throws an error
B). It allows reassignment
C). It assigns the value globally
D). It assigns a default value
What is lexical scoping in JavaScript?
A). Variables scoped to the entire codebase
B). Variables scoped to their functions
C). Variables scoped based on their position in the code
D). Variables scoped based on their names
How can you access a variable declared in an inner block from an outer block?
A). Using the var keyword
B). Using the let keyword
C). Using the const keyword
D). Using the this keyword
Which of the following correctly defines a block scope?
A). A scope that encompasses the entire codebase
B). A scope that encompasses a function
C). A scope that encompasses a block of code delimited by curly braces
D). A scope that encompasses an object
What is the benefit of block scope in loops?
A). It allows variables to be reassigned within each iteration
B). It prevents variable hoisting
C). It restricts variables to the loop block
D). It makes variables globally accessible
What happens if you try to access a block-scoped variable outside its block?
A). The variable is accessible globally
B). The variable is accessible within its block
C). An error occurs
D). The variable is accessible within a function
What is hoisting in JavaScript?
A). Moving variables to the top of their function or global scope
B). Making variables undefined
C). Creating new variables
D). None of the above
What is the output of console.log(blockVar); outside a block if let blockVar = 'Block'; is declared inside a block?
A). Block
B). undefined
C). Error
D). null