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
Which of the following can create a global variable?
A). var
B). let
C). const
D). All of the above
What happens if you declare a variable inside a function with the same name as a global variable?
A). It creates a new local variable
B). It throws an error
C). It modifies the global variable
D). It assigns the global variable to null
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
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 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
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 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
In Node.js, what is the global object called?
A). window
B). global
C). document
D). process