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 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
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 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
Can const variables be reassigned in nested scopes?
A). Yes
B). No
C). Only if they are strings
D). Only in strict mode
What is the scope of a variable declared with let?
A). Global
B). Function
C). Block
D). Object
What will the following code output: { const a = 10; a = 20; }?
A). 10
B). 20
C). undefined
D). TypeError
Which keyword should be used for a variable that might be reassigned?
A). const
B). let
C). var
D). function
Which keyword is used to declare a read-only named constant?
A). let
B). var
C). const
D). static