What is the primary difference between var and let?
A). Scope
B). Initialization
C). Data type
D). Assignment
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
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
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
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 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
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 keyword should be used for a variable that might be reassigned?
A). const
B). let
C). var
D). function
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