1. What is the result of the following code: 'let a = 5; function example() { let a = 10; console.log(a); } example(); console.log(a);'

• 10, 5
• 5, 10
• 10, undefined
• undefined, 5

2. What is the scope of a variable in JavaScript?

• The geographical area where a variable is declared
• The range of values a variable can hold
• The context in which a variable is accessible
• The data type of a variable

3. What is a closure in JavaScript?

• A function that has no access to its own scope
• A function that can access variables from its own scope and the scope in which it was created
• A variable declared inside a loop
• A variable with a constant value

4. Consider the following code: 'function outer() { let x = 10; function inner() { console.log(x); } return inner; } let closureFunc = outer(); closureFunc();'. What will be logged to the console?

• 10
• undefined
• ReferenceError
• outer

5. How can you avoid variable name conflicts in JavaScript?

• By using short and unique variable names
• By using the same variable names in different scopes
• By avoiding the use of functions
• By properly using local and global scopes

6. What is the difference between global scope and local scope in JavaScript?

• Global scope is for variables declared inside a function, local scope is for variables declared outside any function
• Global scope is for variables declared outside any function, local scope is for variables declared inside a function
• There is no difference between global and local scope
• Global scope is for numbers, local scope is for strings

7. What is the 'lexical scope' in JavaScript?

• The scope of a variable defined inside a loop
• The scope of a variable declared using 'let' or 'const'
• The scope determined by the position of the function's definition in the source code
• The scope of a variable passed as an argument to a function

8. How does a closure help with encapsulation in JavaScript?

• By hiding the implementation details of a function
• By making all variables global
• By exposing all variables to the outer scope
• By preventing the use of functions

9. How can you create a private variable in JavaScript using closures?

• By declaring the variable with 'var'
• By using the 'static' keyword
• By declaring the variable inside a function and returning a function that accesses it
• There is no way to create private variables in JavaScript

10. What happens if you try to access a variable outside its scope in JavaScript?

• The variable becomes global automatically
• A new local variable with the same name is created
• An error occurs, and the program stops executing
• The variable loses its value