What keyword is used to ensure a variable is block-scoped?
A). var
B). global
C). let
D). window
What is the global object in a browser environment?
A). window
B). global
C). document
D). this
Which keyword is used to declare a variable in the global scope?
A). let
B). var
C). const
D). function
Which of the following can create a global variable?
A). var
B). let
C). const
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
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
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
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 happens if you declare a variable without var
, let
, or const
inside a function?
A). It becomes a global variable
B). It becomes a local variable
C). It throws an error
D). It becomes a constant
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