下面附题：
NASA's methodical approach to the exploration of Mars has not yet answered the questions of whether biological life forms ever emerged on Mars and whether, presuming such life forms having left fossil traces to begin with, those traces can still exist in some moist recesses of the cold and arid planet.
A. and whether, presuming such life forms having left fossil traces to begin with, those traces can
B. and whether, if it is presumed that such life forms left some fossil traces to begin with, can those traces
C. and whether, presuming such life forms left fossil traces to begin with, those traces
D. and, presuming such life forms did leave some fossil traces to begin with, if they can
E. and, presuming such life forms to have left fossil traces to begin with, if they
OA: C
我选了正确答案，但是是在比较错误选项的结果下得出，我的疑问：
1.正确答案中presuming是否需要逻辑主语，如果需要，修饰的对象是 those traces还是NASA's methodical approach？（尽管从语义角度我认为都不对。）
2.如果不需要，这属不属于特殊用法？比如，类似 comma + including其实修饰的是名词。