Careful study shows that the best athletes win , they think then can win.
A. mostly, because
B. almost; as
C. partly; for
D. nearly; since
网友回答
(答案→)A. mostly, because
B. almost; as
C. partly; for
D. nearly; since
解析：考查副词词义辨析和连词的词义辨析。依据句意前果后因，前面的空应是大多数为佳。