We complain of the darkness in which we live out our lives: we do not understand the nature of existence in general; we especially do not know the relation of our own self to the rest of existence. Not only is our life short, our knowledge is limited entirely to it, since we can see （） back before our birth（）out beyond our death, so that our consciousness is as it were a lightning-flash momentarily illuminating the night, it truly seems as though a demon had maliciously shut off all further knowledge from us so as to enjoy our discomfiture.
A. either；or
B. neither；nor
C. both； and
D. not only；but also