The men lost all desire to return to their homeland.
I'm going to go with B. There are keywords in there. He cannot see at his feet, or the top of his head. He can also see darkness. Being blind is like having your eyes closed forever.
Hope this helps.
I believe the best answer for this question is "entropy." Entropy is a scientific term referring to thermodynamics. It measures both the order and the disorder of a system. Order, or disorder, are both defined by how close the system is to equilibrium. Hope this helps. Also, keep in mind to ask questions in the proper category - this would be most suited to science, rather than English. Thanks.