GRE Text Completion: JiJing 1373-GRE填空机经1373题 - 75IL8OCPN4441H15A

By cosmic standards, Earth and its fellow terrestrial planets are chemical ____________: they consist of primarily four elements (iron, magnesium, silicon, and oxygen) that are rare elsewhere in the universe. A. prototypes B. mavericks C. malefactors D. paragons E. old-timers