'A proposed new style of aircraft, say its proponents, could fly between most points on Earth in under two hours because of its skimming along the top of the atmosphere.' 首先,because of就很不顺眼了,后面表达了忒复杂的意思。其次,its doing显然不对嘛,one's doing?再然后,A用by表达了‘通过什么什么的手段’,D的because of不仅没有表达这层意思海强加了一个因果关系。