Which Statement Concerning Marketing Research Is Most Accurate

Which statement concerning marketing research is most accurate?

A) The primary purpose of marketing research is to collect data for historical purposes.
B) When collecting marketing research, people may be reluctant to tell you what you want to know.
C) Marketing research, if done properly, will always result in a positive marketing result.
D) People are just as able to give accurate information about products they have only heard about as those they have actually used.
E) Among those people who participate in market research studies, there is an almost perfect correlation between a respondent's stated intentions and his/her actual buying behavior.