10. What might be too direct or rude to say if you do not agree with the speaker?
选项：

A:I can see what you mean, but that is not always true because ...;
B:I don't think you can get such a conclusion by this research.;
C:You were doing great in making this survey, but I am not very sure if this topic is supported with evidence.;
D:I like your topic, but I am afraid that there was a flaw in your research design that made you unable to obtain valid results.