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
What will the following code output: { const a = 10; a = 20; }?
A). 10
B). 20
C). undefined
D). TypeError
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
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 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 should be used for a variable that might be reassigned?
A). const
B). let
C). var
D). function
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 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 scope of a variable declared with let?
A). Global
B). Function
C). Block
D). Object