OG5 阅读 Q36

Choice B is the best answer. One question Watts asks in regard to the experiment is whether the results would hold true on a larger scale. The passage quotes him in lines 74-76("conclusion...the"): "[But] one question is whether the positive [herding] bias is specific to this site' or true in general." Doing the experiment again but collecting ratings on multiple websites would address Watts's question, as it would show whether or not the same results occur on other sites. 
Choices A, C, and D are incorrect. Providing fewer fake positive comments during the experiment (choice A), requiring users to be registered on the website (choice C), or telling users that their answers will be studied (choice D) are actions that likely would affect the results of the experiment involving users voting on comments about stories on one news website, but they would not address Watts's questions about whether the study would produce the same results on other websites or why different categories of news items had different effects on the news website.