Can const be used for objects and arrays?

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

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

Which keyword allows block-level scope in ES6?

A). var

B). let

C). function

D). var and function

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

A). 5

B). 10

C). undefined

D). ReferenceError

What is the primary difference between var and let?

A). Scope

B). Initialization

C). Data type

D). Assignment

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 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

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

A). SyntaxError

B). TypeError

C). ReferenceError

D). No error

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

Can const variables be reassigned in nested scopes?

A). Yes

B). No

C). Only if they are strings

D). Only in strict mode