We have always assumed that the poor are poor because of circumstances, ________, and background. A: upsetting B: upwelling C: upbringing D: updating

The biggest difference of Arctic （北极）and Antarctic（南极） is A: The Arctic is the ocean surrounded by land, and the Antarctic is the land surrounded by ocean B: Arctic is bigger than Antarctic C: Arctic is warmer than Antarctic D: Upwelling is mostly at Arctic