TOEFL Reading: ETS-TOEFL阅读机经 - MDMJN84X633VO025L$

According to paragraph 2, what is one difference between Earth and Venus? A. Earth has less water in its atmosphere than Venus does. B. Earth has a hydrologic system, but Venus does not. C. Earth is less geologically active than Venus is. D. Earth has more carbon dioxide than Venus does.