47. According to scientists at the University of California, the pattern of changes that have occurred in human DNA over the millennia indicate the possibility that everyone alive today might be descended from a single female ancestor who lived in Africa sometime between 140,000 and 280,000 years ago. (A) indicate the possibility that everyone alive today might be descended from a single female ancestor who (B) indicate that everyone alive today might possibly be a descendant of a single female ancestor who had (C) may indicate that everyone alive today has descended from a single female ancestor who had (D) indicates that everyone alive today may be a descendant of a single female ancestor who(D) (E) indicates that everyone alive today might be a descendant from a single female ancestor who
请教E为什么错,may be might be 如何选择?时态怎么确定? |