题目解析：
【题目翻译】根据第6段，为什么在既缺乏大气层，又缺乏表面或地下液体介质的任何行星上都不可能发现生命？
A：有机分子必须用液体表面层来防止太阳辐射。
B：缺乏这两种特征的行星可能太小了，不能被携带有机物质的许多小行星或彗星击中。
C：有机分子需要液体或气体环境使它们结合在一起，这样它们才能相互作用。
D：需要大气层来保护有机分子免受小行星和彗星的破坏。
【判断题型】题目问的是文章中的具体细节信息，故根据题目问法可以判断本题为事实信息题。
【关键词定位】Each body should have received at least some organic molecules. However, these molecules tend to be destroyed by solar radiation on surfaces unprotected by atmospheres. Moreover, while these molecules might stay intact beneath the surface (as they evidently do on asteroids and comets), they probably cannot react with each other unless some kind of liquid or gas is available to move them about。
【逻辑分析】根据定位句分析，每个个体至少应该接受一些有机分子。 然而，这些分子往往被不受大气保护的表面上的太阳辐射破坏。此外，尽管这些分子可能会在表面下保持完整（因为它们明显对小行星和彗星有影响），但除非某种液体或气体可用于移动它们，否则它们可能无法相互反应”，即气体和液体的环境，对于有机分子的合成是非常重要的。
【选项分析】
A选项的意思为：有机分子必须由液体层的表面保护其不受太阳射线的辐射； A选项虽然说法正确，但是，题目问的是“为什么在缺少大气层和液体介质的行星上不可能发现生命？”显然，答非所问，则A项不正确；
B选项的意思为：不具备这两个特点的行星有可能因为太小以至于会被带有有机物质的陨石和彗星所击中； B选项，第六自然段并没有提到相关的观点，属于无中生有，则B项不正确；
C选项的意思为：有机分子需要有一个液体或者气体环境，使得它们能够相互反应； C项正确。
D选项的意思为：对于保护有机分子不被陨石或者彗星所损坏来说大气层是非常重要的。 由“ these molecules tend to be destroyed by solar radiation on surfaces unprotected by atmospheres”可知，有机分子会收到太阳射线的损坏，并不是陨石和彗星。 D项也不正确。
Studies of meteorites and comets suggest that organic molecules are widespread among both asteroids and comets. Because each body in the solar system was repeatedly struck by asteroids and comets during the period known as the heavy bombardment (about 4 billion years ago), each body should have received at least some organic molecules. However, these molecules tend to be destroyed by solar radiation on surfaces unprotected by atmospheres. Moreover, while these molecules might stay intact beneath the surface (as they evidently do on asteroids and comets), they probably cannot react with each other unless some kind of liquid or gas is available to move them about. Thus, if we limit our search to worlds on which organic molecules are likely to be involved in chemical reactions, we can probably rule out any world that lacks both an atmosphere and a surface or subsurface liquid medium, such as water. 
