What will be the output of the following code: let x = 10; { let x = 20; } console.log(x);?

What is the primary difference between var and let?

A). Scope

B). Initialization

C). Data type

D). Assignment

Which keyword is used to declare a read-only named constant?

A). let

B). var

C). const

D). static

What is the value of a const variable once it is assigned?

A). Can be changed later

B). Cannot be changed later

C). Depends on the data type

D). Undefined initially

Can const variables be reassigned in nested scopes?

A). Yes

B). No

C). Only if they are strings

D). Only in strict mode

Which keyword should be used for a variable that might be reassigned?

A). const

B). let

C). var

D). function

What is the temporal dead zone in ES6?

A). Time between function calls

B). Period between variable declaration and initialization

C). Time between two loops

D). Interval between event listeners

Can a let variable be redeclared in the same scope?

A). Yes

B). No

C). Only if it is a string

D). Only if it is a number

What error will the following code produce: const PI; PI = 3.14;?

A). SyntaxError

B). TypeError

C). ReferenceError

D). No error

What is the scope of a variable declared with let?

A). Global

B). Function

C). Block

D). Object

What happens if you try to access a let variable before its declaration?

A). Returns undefined

B). Throws a ReferenceError

C). Returns null

D). Returns an empty string