What is the primary difference between var and let?

Which keyword allows block-level scope in ES6?

A). var

B). let

C). function

D). var and function

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

A). let

B). var

C). const

D). static

What is the scope of a variable declared with let?

A). Global

B). Function

C). Block

D). Object

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 a variable declared with let be hoisted?

A). Yes, partially

B). No

C). Yes, fully

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

Are variables declared with let and const accessible before they are declared?

A). Yes

B). No

C). Only in strict mode

D). Only if they are numbers

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

A). const

B). let

C). var

D). function

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