Which of the following is unique to a Windows PC game compared to games played on the
Xbox 360 or Windows Phone 7?

A.
Multiple players can connect and play by using the Internet.

B.
Updates can be downloaded and installed when necessary.

C.
Game results and achievements can be posted to online leaderboards.

D.
Complex input is available by using the mouse, keyboard, or handheld controllers.

Explanation:
http://msdn.microsoft.com/en-us/library/bb203903.aspx