I understand that your book contains many sample questions in a multiple-choice format. One difficulty in writing test question is that the issues of enterprise architecture intersect and interweave in complex ways. The "wrong" answers must be demonstrably less preferable than the right one(s), and yet the question must not make the "right" answer too obvious. So some ambiguity may be needed in crafting a question... but not too much!
Was there one topic in particular for which it seemed more difficult to craft effective multiple choice questions?