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
What is the benefit of block scope in JavaScript?
A). It reduces variable conflicts
B). It increases global scope
C). It simplifies variable declarations
D). It makes variables inaccessible
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 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
What is the output of console.log(i); outside the loop if let i = 10; is declared inside a loop?
A). 10
B). undefined
C). Error
D). 0
How does block scope help prevent variable hoisting issues?
A). By moving variables to the top of the code
B). By restricting variables to their block
C). By making variables accessible globally
D). By assigning default values to variables
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
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
Which keyword introduces block-scoped variables in JavaScript?
A). var
B). let
C). const
D). function
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