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

Which keyword allows block-level scope in ES6?

A). var

B). let

C). function

D). var and function

What is the scope of a variable declared with let?

A). Global

B). Function

C). Block

D). Object

Can a variable declared with let be hoisted?

A). Yes, partially

B). No

C). Yes, fully

D). Only in strict mode

Which of the following statements about const and objects is true?

A). Objects declared with const are immutable

B). Properties of objects declared with const can be changed

C). The reference of objects declared with const can be changed

D). const cannot be used with objects

Can const variables be reassigned in nested scopes?

A). Yes

B). No

C). Only if they are strings

D). Only in strict mode

What is the output of the following code: let z = 3; z = 5; console.log(z);?

A). 3

B). 5

C). undefined

D). ReferenceError

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

Can const be used for objects and arrays?

A). No

B). Yes

C). Only for arrays

D). Only for objects

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

A). let

B). var

C). const

D). static

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

A). const

B). let

C). var

D). function