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

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

A). 10

B). 20

C). undefined

D). TypeError

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

A). SyntaxError

B). TypeError

C). ReferenceError

D). No error

Can const be used for objects and arrays?

A). No

B). Yes

C). Only for arrays

D). Only for objects

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

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 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