Which keyword allows block-level scope in ES6?

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

A). 10

B). 20

C). undefined

D). ReferenceError

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 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

What will the following code output: { const a = 10; a = 20; }?

A). 10

B). 20

C). undefined

D). TypeError

What will the following code output: { let y = 5; { let y = 10; console.log(y); } }?

A). 5

B). 10

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

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

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

A). const

B). let

C). var

D). function

Can const be used for objects and arrays?

A). No

B). Yes

C). Only for arrays

D). Only for objects

Can a const variable be declared without an initial value?

A). Yes

B). No

C). Only in strict mode

D). Only if it is an object