A.Line1.X1=Line2.X2且Line1.Y1=Line2.Y2
B.Line1.X1=Line2.Y1且Line1.Y1=Line2.X1
C.Linel.X2=Line2.X1且Line1.Y1=Line2.Y2
D.Line1.X2=Line2.X1且Line1.Y2=Line2.Y2