[求助]请教费费逻辑的一道题 95

选 assumption GAP型95. Scientific research that involves international collaboration has produced papers of greater influence, as measured by the number of times a paper is cited in subsequent papers, than has research without any collaboration. Papers that result from international collaboration are cited an average of seven times, whereas papers with single authors are cited only three times on average. This difference shows that research projects conducted by international research teams are of greater importance than those conducted by single researchers. 被引用的多推出重要，
Which one of the following is an assumption on which the argument depends? b
(A) Prolific writers can inflate the number of citations they receive by citing themselves in subsequent papers.
(B) It is possible to ascertain whether or not a paper is the product of international collaboration by determining the number of citations it has received.
(C) The number of citations a paper receives is a measure of the importance of the research it reports.
(D) The collaborative efforts of scientists who are citizens of the same country do not produce papers that are as important as papers that are produced by international collaboration
(E) International research teams tend to be more generously funded than are single researchers.
正确选项是B，同意，但是我有个疑问就是D项中的The collaborative efforts of scientists who are citizens of the same country是不是和single authors一个概念？如果是的话可否做他因解题，谢谢