问题详情

During the day，a vessel picking up a submarine cable shall carry ().

A.Three shapes，the highest and lowest shall be red balls，and the middle shall be a white diamond

B.Two black balls

C.Three shapes;the highest and lowest shall be black balls，and the middle shall be a red diamond

D.Three shapes;the highest and lowest shall be black balls and the middle shall be a black diamond

请帮忙给出正确答案和分析，谢谢！