The number of foreign students attending Chinese universities rising steadily since 1990.
A. have been
B. are
C. has been
D. is
网友回答
A. have been
B. are
(答案→)C. has been
D. is
解析：考查主谓一致和时态。本题的主语是the number of..指…的数量；该短语做主语是，谓语动词用单数，排除AB。再根据since 1990说明使用的现在完成时，故C正确。