var can create a global variable when declared outside any function. let and const do not create global object properties.
What is the global object in a browser environment?
A). window
B). global
C). document
D). this
How can you access a global variable inside a function if it has the same name as a local variable?
A). By using the window object
B). By using the global object
C). By using a different name for the global variable
D). By using the this keyword
What is the output of typeof window in a browser environment?
A). object
B). undefined
C). function
D). global
Which of the following methods can help in avoiding global variables?
A). Using functions to encapsulate code
B). Using objects to namespace code
C). Using ES6 modules
D). All of the above
What is the output of console.log(window.globalLet); if let globalLet = 'Hello'; is declared in the global scope?
A). Hello
B). undefined
C). error
D). null
Which statement is true about global variables in JavaScript?
A). They are not accessible inside functions
B). They can be accessed and modified from any part of the code
C). They are constants
D). They can only be read, not modified
What keyword is used to ensure a variable is block-scoped?
A). var
B). global
C). let
D). window
In Node.js, what is the global object called?
A). window
B). global
C). document
D). process
How can you avoid global scope pollution?
A). By using local variables
B). By using IIFE (Immediately Invoked Function Expressions)
C). By using modules
D). All of the above
What will be the output of console.log(window.myVar); if var myVar = 'Hello'; is declared outside any function?
A). Hello
B). undefined
C). error
D). null