You are troubleshooting a web page that includes the following code segment.

You need to evaluate the value of the variable x.

What will be displayed in the user interface?

A. 0

B. 1

C. 2

D. An error

Explanation:

* Alert(x) is within the scope of the outermost assignment, x=0.

* Local variables have local scope: They can only be accessed within the function.

Example

// code here can not use carName

function myFunction() {

var carName = -Volvo-;

// code here can use carName

}

* Avariable declared outside a function, becomes GLOBAL.

A global variable has global scope: All scripts and functions on a web page can access it.

Example

var carName = – Volvo-;

// code here can use carName

function myFunction() {

// code here can usecarName

}

* The alert() method displays an alert box with a specified message and an OK button.

An alert box is often used if you want to make sure information comes through to the user.

Reference: JavaScript Scope