下列图形中,请选择ABCD-U8b*h6o8^3M.}不是四边形。0Z4I(m2\3S-w4g
A:长方形0Z4I(m2\3S-w4g
B:三角形0Z4I(m2\3S-w4g
C:正方形0Z4I(m2\3S-w4g
D:平行四边形0Z4I(m2\3S-w4g