which two properties in Microsoft.Xna.Framework.Game controls the automatic frame rate setting?

In an XNA game, which two properties in Microsoft.Xna.Framework.Game controls the
automatic frame rate setting? (Choose two.)

A.
GameTime

B.
IsFixedTimeStep

C.
TargetElapsedTime

D.
Content

Explanation:
http://msdn.microsoft.com/en-us/library/microsoft.xna.framework.game_members.aspx