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

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

A). 5

B). 10

C). undefined

D). ReferenceError

Can const be used for objects and arrays?

A). No

B). Yes

C). Only for arrays

D). Only for objects

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

A). SyntaxError

B). TypeError

C). ReferenceError

D). No error

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

A). 3

B). 5

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

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 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 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

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