var outside of any function declares a global variable, whereas let and const do not create properties on the global object.
Can global variables lead to name collisions in large codebases?
A). Yes
B). No
C). Only if not managed properly
D). Only in strict mode
Can a global variable be accessed inside a function?
A). Yes
B). No
C). Only if passed as a parameter
D). Only if defined with var
What is the output of console.log(globalThis === window); in a browser environment?
A). 1
B). 0
C). undefined
D). null
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
Which of the following can be used to prevent accidental modification of global variables?
A). Encapsulation
B). Namespace
C). Strict mode
D). Block scoping
Which of the following can create a global variable?
A). var
B). let
C). const
D). All of the above
What is the output of console.log(globalVar); if globalVar = 'Hello'; is assigned inside a function without using var, let, or const?
A). Hello
B). undefined
C). error
D). null
How do you declare a global variable inside a function?
A). Using var
B). Using let
C). Using const
D). Assigning to window
What keyword is used to ensure a variable is block-scoped?
A). var
B). global
C). let
D). window
What is the output of typeof window in a browser environment?
A). object
B). undefined
C). function
D). global