绘制一个实心圆，下列代码正确的是 A: Graphics g=CreateGraphics();Pen myPen=new Pen(Color.Blue);g.DrawEllipse(myPen, new Rectangle(50, 50, 100, 100)); B: Graphics g=CreateGraphics();SolidBrush myBrush = new SolidBrush(Color.Blue);g.DrawEllipse(myBrush, new Rectangle(50, 50, 100, 100)); C: Graphics g=CreateGraphics();SolidBrush myBrush = new SolidBrush(Color.Blue); g.FillEllipse(myBrush, new Rectangle(50, 50, 100, 100)); D: Graphics g=CreateGraphics();Pen myPen=new Pen(Color.Blue);g.FillEllipse(myPen, new Rectangle(50, 50, 100, 100));