Can a variable declared with let be hoisted?
A). Yes, partially
B). No
C). Yes, fully
D). Only in strict mode
What will the following code output: { const a = 10; a = 20; }?
A). 10
B). 20
C). undefined
D). TypeError
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 const variable be declared without an initial value?
A). Yes
B). No
C). Only in strict mode
D). Only if it is an object
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
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 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 error will the following code produce: const PI; PI = 3.14;?
A). SyntaxError
B). TypeError
C). ReferenceError
D). No error