Examining the influence of the printing press and printed books in Europe would most likely be enhanced by looking at documents from the period that discuss or demonstrate the effects of this new technology directly. Among the options provided:
a) A diagram created by Johannes Gutenberg would show the mechanics of the printing press, which could be useful in understanding the technology, but it would not necessarily reflect the broader impact on Europe.
b) A twentieth-century map showing the printing presses in Renaissance Europe might help understand the spread and locations of printing presses, but being a modern representation, it is not a primary source from the time period in question.
c) A copy of an illuminated manuscript could serve as an example of what book production looked like before the printing press, which would provide contrast to after the press's invention. However, it does not directly show the influence of the printing press.
d) A sixteenth-century document calling for the censorship of newly printed books would be a primary source directly related to the influence of the printing press and printed books. This could illustrate concerns about the spread of information due to the printing press and the attempts to control its effects.
Therefore, the best option to understand the influence of the printing press and printed books in Europe would be:
d) a sixteenth-century document calling for the censorship of newly printed books.