the third one

antonia

P51 236
  Unlike other arachnids, which have their nerve cells evenly distributed along their [U]bodies, the scorpion’s nerve cells are clustered in its head, like a mammal’s.[/U](C)body, the scorpions has a cluster of nerve cells in its head, as a mammal does.
选了C，但their后面怎么是单数body; scorpions是复数，后面怎么跟了has?!
不解。

jimmy221

这是个逻辑问题。他们的细胞只可能分布在他们各自的身体里。