问题补充：
While we are having an exam, it is not proper to our notes or dictionaries.
A. refer to
B. lead to
C. whisper to
D. react to
答案：
(答案→)A. refer to
B. lead to
C. whisper to
D. react to
解析：
这题考查词组辨析：refer to参考，所指，lead to通向，导致，whisper to向…低语， react to对…做出反应，句意是：当我们考试时，参考笔记或查字典是不合适的。选A。
