题目下列各组长度的333条线段,不能构成三角形的是( )A.3cm3cm3cm,5cm5cm5cm,7cm7cm7cmB.5cm5cm5cm,4cm4cm4cm,9cm9cm9cmC.4cm4cm4cm,6cm6cm6cm,9cm9cm9cmD.2cm2cm2cm,3cm3cm3cm,4cm4cm4cm知识点:三角形的三边关系章节:未标注