
Passage: An authoritative opinion poll conducted an investigation into the causes of the "9/11" terrorist attacks around the world and found that 40% thought it was caused by the unfair foreign policy of the United States, 55% thought it was caused by the conflict between Islamic civilization and Western civilization, 23% thought it was caused by the evil nature of terrorists, and 19% did not express their opinions.
Question: Which of the followings is the most reasonable explanation, and the above seems to contain contradictory statements?
A. A.The sampling of survey samples is not random, so it is not representative
B. B.Some respondents later changed their views
C. C.Many respondents believe that the causes of the "9/11" terrorist attacks are not single, but complex
D. D.There was a technical error in the calculation of the survey results
Answer: