题目选项分析

Rather than more distant planets, the atmospheres of planets within the habitable zone, the shell-shaped region of space surrounding a star within which a planet could maintain liquid water on its surface, are much more likely to contain water and, possibly, multicellular life.

Planets within the habitable zone, the shell-shaped region of space surrounding a star within which a planet could maintain liquid water on its surface, are much more likely than more distant planets to harbor atmospheres which contain water and, possibly, multicellular life.