B) The most dangerous thing for these remote island dwellers is land erosion.

B) 对于这些偏远岛屿居民来说，最危险的事情是土地侵蚀。

We have land erosion, the sea is taking most of the lands and people here try whatever they have to build sea walls.

土地被侵蚀，海水侵蚀了大部分土地，这里的人们想尽一切办法来建造海堤。