The answer is A. Because all the remaining answers are good examples of how people could generally cut back on their use of oil. And if your family moves father away from where you work, you will need to travel longer distances, and thus use more oil, which is opposite of what you are trying to do.
The meaning of remarkable is worthy of attention; striking and meaning of ordinary is with no special or distinctive features; normal. so it is the opposite of remarkable
The "great packing machine" refers to the slaughter industry the author describes through the book. He is trying to portrait and denounce the unhealthy, dangerous, almost-enslavement condition the workers suffer in that industry.
