单选题 Evidence, reference, and footnotes by the thousand testify to a scrupulous researcher who does considerable justice to a full range of different theoretical and political positions.

【正确答案】 D
【答案解析】scrupulous小心谨慎的；meticulous小心翼翼的；trustworthy可信赖的；intelligent聪明的；diligent勤勉的。