单选题 The author believes that our knowledge of social systems is more secure than that of physical systems because ______.

A、 it is not based on personal experience
B、 new discoveries are less likely to occur in social sciences
C、 it is based on a fairly representative quantity of data
D、 the records of social systems are more reliable

【正确答案】 D

【答案解析】[试题分析] 本题为作者观点题。
[详细解答] 从文中Our image of the astronomical universe is the least secure of all simply because we observe such a fantastically small sample of it and its record-keeping is trivial as compared with the rich records of the social systems及其上下文可以判断，社会科学之所以更可靠些是因为可供研究的records更多，也就更全面。因此D项符合作者观点。