You are developing a Windows Store app.
The app will access several web resources that use an OAuth 2.0 authentication provider.
You need to recommend in which class to store user credentials so that users do not have to
reenter their credentials when they access the web resources.
Which class should you recommend?

A.
windows.Security.Authentication.Onlineld.OnlineldAuthenticator

B.
Windows.Security.Credentials.UI.CredentialPicker

C.
system.Net.NetworkCredential

D.
windows.Security.Credentials.PasswordVault

Explanation:

The task of storing and retrieving user credentials securely and allowing user credentials
roam at no cost with the user’s Microsoft account is simplified with the Credential Locker.
Storing user credentials in the Credential Locker is a quick, two-step process.
1.Obtain a reference to the Credential Locker using the PasswordVault object from the
Windows.Security.Credentials namespace.
2.Create a PasswordCredential object that contains an identifier for your app, the username
and the password, and pass that to the PasswordVault.Add method to add the credential to
the locker.