组图1： ■□■□    □■■□      □□■■

组图2：   ●                      ○                ●
        ●●●                  ○○○            ●  ●
      ●●●●●              ○○○○○             ●
    ●○○○○○○          ○●●●●●●          ●
  ●●●○○○○○○      ○○○●●●●●●
●●●●●○○○○○○  ○○○○○●●●●●●      ●

请根据组图1，判断上面组图2最后一个问号应该是下面哪个图？
          ○                            ○
        ○○○                        ○○○
      ○○○○○                    ○○○○○
    ○○○○○○○                ○●●●●●○
  ○○○○○○○○○            ○○○●●●○○○
○○○○○○○○○○○        ○○○○○●○○○○○
          A                             B
          ●                            ●
        ●●●                        ●●●
      ●●●●●                    ●●●●●
    ●●●●●●●                ●○○○○○●
  ●●●●●●●●●            ●●●○○○●●●
●●●●●●●●●●●        ●●●●●○●●●●●
          C                             D