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 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
What will the following code output: { const a = 10; a = 20; }?
A). 10
B). 20
C). undefined
D). TypeError
What is the output of the following code: let z = 3; z = 5; console.log(z);?
A). 3
B). 5
C). undefined
D). ReferenceError
Can a variable declared with let be hoisted?
A). Yes, partially
B). No
C). Yes, fully
D). Only in strict mode
Can const variables be reassigned in nested scopes?
A). Yes
B). No
C). Only if they are strings
D). Only in strict mode
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 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
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 error will the following code produce: const PI; PI = 3.14;?
A). SyntaxError
B). TypeError
C). ReferenceError
D). No error