Counterclockwise (default), small arc (default)

   
   
<Canvas xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">


    <Path Stroke="Red" StrokeThickness="3">
        <Path.Data>
            <PathGeometry>
                <PathFigure StartPoint="144 144">
                    <ArcSegment Point="240 240" Size="144 96"
                                RotationAngle="45" />
                </PathFigure>
            </PathGeometry>
        </Path.Data>
    </Path>

</Canvas>