标题: 【求助】GWD2-34 [打印本页] 作者: glitters 时间: 2010-2-8 19:00 标题: 【求助】GWD2-34 Q6 :TT-GWD2-34. NASA’s methodicalapproach to the exploration of Mars has not yet answered the questions ofwhether biological life forms ever emerged on Mars and whether, presumingsuch life forms having left fossil traces to begin with, those traces canstill exist in some moist recesses of the cold and arid planet.
A. andwhether, presuming such life forms having left fossil traces to begin with,those traces can B. andwhether, if it is presumed that such life forms left some fossil traces tobegin with, can those traces C. andwhether, presuming such life forms left fossil traces to begin with, thosetraces D. and,presuming such life forms did leave some fossil traces to begin with, if theycan E. and,presuming such life forms to have left fossil traces to begin with, if they 答案：C