Which two operating system user input services are available for your Windows Phone 7 game?

Which two operating system user input services are available for your Windows Phone 7
game? (Choose two.)

A.
Selectors

B.
Choosers

C.
Pickers

D.
Launchers

Explanation:
http://msdn.microsoft.com/library/windows/apps/ff769542(v=vs.105).aspx