How to add the answer to the randomizer?

could u help me please? I have a randomizer, when I click on the button a random answer appears. But I want to create a button that complements the answer options in the randomizer. How to do it?

        String Text1 = "Yes";
        String Text2 = "No";
        String Text3 = "Maybe Yes";
        String Text4 = "Maybe No";
        String Text5 = "Probably";
        String Text6 = "Have a chance";
        String Text7 = "Answer isn't correct";
        PointF pos;
        PointF Location = new PointF(ClientSize.Width / 2, ClientSize.Height / 2);
        Color TextColor = Color.White;
        pos = Location;
        var brush = new SolidBrush(TextColor);
        var rect = new RectangleF(pos.X - 200, pos.Y - 200, 2 * 200, 2 * 200);
        Random rnd = new Random();
        int num = rnd.Next(7);
        Font Font = new Font("Arial", 16);
        Refresh();
        switch (num)
        {
            case 0:
                g.DrawString(Text1, Font, brush, rect, new StringFormat { Alignment = StringAlignment.Center, LineAlignment = StringAlignment.Center });
                break;
            case 1:
                g.DrawString(Text2, Font, brush, rect, new StringFormat { Alignment = StringAlignment.Center, LineAlignment = StringAlignment.Center });
                break;
            case 2:
                g.DrawString(Text3, Font, brush, rect, new StringFormat { Alignment = StringAlignment.Center, LineAlignment = StringAlignment.Center });
                break;
            case 3:
                g.DrawString(Text4, Font, brush, rect, new StringFormat { Alignment = StringAlignment.Center, LineAlignment = StringAlignment.Center });
                break;
            case 4:
                g.DrawString(Text5, Font, brush, rect, new StringFormat { Alignment = StringAlignment.Center, LineAlignment = StringAlignment.Center });
                break;
            case 5:
                g.DrawString(Text6, Font, brush, rect, new StringFormat { Alignment = StringAlignment.Center, LineAlignment = StringAlignment.Center });
                break;
            case 6:
                g.DrawString(Text7, Font, brush, rect, new StringFormat { Alignment = StringAlignment.Center, LineAlignment = StringAlignment.Center });
                break;
        }