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 is the primary difference between var and let?
A). Scope
B). Initialization
C). Data type
D). Assignment
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
What is the scope of a variable declared with let?
A). Global
B). Function
C). Block
D). Object
What is the output of the following code: let z = 3; z = 5; console.log(z);?
A). 3
B). 5
C). undefined
D). ReferenceError
What is the temporal dead zone in ES6?
A). Time between function calls
B). Period between variable declaration and initialization
C). Time between two loops
D). Interval between event listeners
Which keyword allows block-level scope in ES6?
A). var
B). let
C). function
D). var and function
Can const variables be reassigned in nested scopes?
A). Yes
B). No
C). Only if they are strings
D). Only in strict mode
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
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