C. The higher the surface gravity, the higher the escape velocity
D. The less the atmosphere contributes to the total mass, the lower the temperature
答案是C 我选的D 不知道为什么啊
The Jovian planets, because of their greater masses and thus higher surface gravities, have higher escape velocities (21-60 kilometers per second) than the terrestrial planets.
根据这句话C是对的greater masses higher surface gravities higher escape velocities
我不知道为什么可以选D,我只是谈一下我的理解,首先根据重点句,at the low temperatures of the Jovian planets even the lightest gases are unlikely to acquire the speed needed to escape
是Jovian planets的low temperature 导致没有speed可以escape。 这是关键推理依据。
然后The slightly larger terrestrial planets Earth, Venus, and Mars retain some heavy gases like carbon dioxide, but even their atmospheres make up only an infinitesimally small portion of their total mass.中的Earth, Venus, and Mars ,是代表 terrestrial planets这类行星的,与Jovian planets对立,那么不管这句话要怎么理解,必然与上面的相反,结论必然是high tempurate有关的说法, 所以D应该可以考直觉排除。 如果细看的话就是earth留住了一些heavy gases,但这类heavy gases只是少比例,这还是说明earth是high temperature,所以我认为不该选D