A. It doesn't exactly say that they were horrified by the use of the book. But it does say remarkably they were allowed in to see it. This could mean that something was being done with the book that the Dutch may not like.
B. It doesn't say that they are proud of the way they are using the book and the evidence from the text actually refutes that. If they were proud wouldn't they let everyone in to see the way they were using the book? Obviously they aren't proud if they are attempting to hide the way it's being used.
C. It doesn't say this either. And the way the book is treated would not deeply hurt the Americans as much as the Dutch. Plus they aren't allowed in to see it.
D. They are only letting in the dutch as it says from the text.
