When he said that he means that he feels tired and out of sorts.
Meaning that mans progress (maybe) is mostly driven by his needs and greed for the material things in life.
As per assembling a writing plan for an essay, the better answer, if not the best, would be B. Material that catches the reader's interest.
Many would argue that the correct answer would be D. the general idea of your essay or maybe C. a brief summary of your conclusion or perhaps A. the first section of the body of your essay. Well, they are all correct. As long as what follows is duly taken noted and is consistent to keep the flow of the essay that when the final paper is read, it isn't confusing in any way. Though generally speaking, what should come first would be the material that catches the reader's interest.
6-3x=5x-10x+2
Add 5x and -10x and you get -5x
6 - 3x = -5x + 2 ( add -5 to the other side)
6+2x=2
now subtract 6 from both sides
2x = -4
divide both sides by 2 to get x by itself
x=-2