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 will the following code output: { let y = 5; { let y = 10; console.log(y); } }?
A). 5
B). 10
C). undefined
D). ReferenceError
Which keyword should be used for a variable that might be reassigned?
A). const
B). let
C). var
D). function
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
What error will the following code produce: const PI; PI = 3.14;?
A). SyntaxError
B). TypeError
C). ReferenceError
D). No error
What is the scope of a variable declared with let?
A). Global
B). Function
C). Block
D). Object
What is the primary difference between var and let?
A). Scope
B). Initialization
C). Data type
D). Assignment
Which keyword is used to declare a read-only named constant?
A). let
B). var
C). const
D). static
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
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