单项选择题

A. Add a property trigger to the Triggers collection of ManageOrders.   Configure the property trigger to be based on the IsPressed property of showOtherSide. 
B. Add an event trigger to the Triggers collection of ManageOrders.   Configure the event trigger to be based on the Click event of showOtherSide.
C. Call the BeginAnimation method of showOtherSide.   Pass FlipSides as a parameter of the BeginAnimation method. 
D. Call the BeginAnimation method of ManageOrders.   Pass FlipSides as a parameter of the BeginAnimation method.