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Question 1:  Which keyword is used to declare a variable in JavaScript?

(A) var

(B) let

(C) Both A and B

Question 2:  What is the main difference between var and let?

(A) let allows redeclaration var does not

(B) var is function-scoped let is block-scoped

(C) Both have the same behavior

Question 3:  Which statement is true about const variables in JavaScript?

(A) Their values can be reassigned

(B) They must be initialized when declared

(C) They are the same as var

Question 4:  What will happen if you try to redeclare a let variable in the same scope?

(A) It will throw an error

(B) It will overwrite the previous value

(C) It will be ignored

Question 5:  What is the scope of a var variable?

(A) Function scope

(B) Block scope

(C) Global scope only

Question 6:  What will be the output of the following code?

(A) 10

(B) 20

(C) Error

Question 7:  Can a const variable hold an object that can be modified?

(A) Yes but the reference cannot be changed

(B) No the object itself cannot be modified

(C) Yes both reference and object can be changed

Question 8:  What happens if you try to use a variable before declaring it with let?

(A) It returns undefined

(B) It throws a ReferenceError

(C) It assigns null

Question 9:  Which of the following is NOT a valid variable name in JavaScript?

(A) myVar

(B) 2ndVariable

(C) _name

Question 10:  What is the default value of an uninitialized let variable?

(A) null

(B) undefined

(C) 0