In the second paragraph, the author is primarily concerned with A. arguing in favor of a particular theory about the formation of the Earth-Moon system. B. summarizing conventional theories about the formation of the earth-Moon system. C. anticipating and responding to criticisms of a particular theory about the formation of the Earth-Moon system. D. explaining why the Earth-Moon system is considered scientifically perplexing. E. questioning an assumption underlying one theory about the formation of the Earth-Moon system.