Which of the Following Statements Is True

Which of the following statements is true?

A) Scientists typically use different methods to conduct research,which explains why studies involving humans often have conflicting results.
B) Scientists developed dietary recommendations for the U.S.population after analyzing results of a single American study,the Framingham Heart Study.
C) Scientists have peer reviewers analyze the designs of their human research studies,because the peer-review process reduces research bias.
D) Scientists are unlikely to obtain money to conduct research,if they don't respect the opinions and beliefs of the people in agencies who fund such projects.