Mr. Grave wanted the other members of the donner party to eat the flesh of his body once he died, so they could live. They were put into horrible conditions and their supplies were already run out weeks ago. To the group of pioneers it seemed that there was nothing to do for living but kannibalism, so they ate fleshes of the dead. Therefore, Mr. Grave was ready to make such a sacrifice, hoping that he can save lives.
William meant that the daffodils looked like they were dancing.
So the correct answer is D.
Hope this helps,
Davinia.
