They will start to adapt to life on the island
During metaphase 1, the spindle fibers attach to the centromeres of each chromosome. Both kinetochores of each sister chromatid pair are turned toward the same pole. And 2 members of each chromosome pair (sister chromatids) are pulled into each new cell during anaphase 1.
I think the answer you want is they are called chromatids.
I honestly think that a or d would be the best options. I would start with D and if that doesn't work try a.