Waikiki notices that there are mosquito larvae collecting in the pond. Nobody wants a mosquito infestation, so the villagers decide that they should try to do something about them.

Options were to put soap in the pond or to put oil in the pond.

I chose soap: After putting soap in the pond the tribe discovers that the only effect of adding soap is that they are being eaten alive by very clean mosquitoes.

I'm not sure if the fact that the mosquitoes were biting them made a difference but many of the villagers were sick after I chose the option.