You need to identify whether the app has permission to use the webcam

You are developing a Windows Store app that will access a device’s webcam. All necessary
device capabilities have been declared in the app manifest.
The app must not throw an error if the user has declined or revoked permission to the
webcam.
You need to identify whether the app has permission to use the webcam.
What should you do?

A.
Using the CameraCaptureUI class, test for the value returned by the CaptureFileAsync
method.

B.
Using the CameraCaptureUI class, test for the value returned by the videoSettings
property.

C.
Using the MediaCapture class, test for the value returned by the async method.

D.
Using the MediaCapture class, test for the value returned by the MediaCaptureSettings
property.

Explanation:

Reference:
http://msdn.microsoft.com/en-us/data/windows.media.capture.mediacapture