Answer: I would contend that the right answer is the A. Spanish royal council meeting notes concerning strategies for defeating Muslims.
Explanation: Just to elaborate a little on the answer, it can be added that, on the one hand, it is said that "European leaders concluded that [...]," and, on the other hand, it is said that "Visionary Europeans hoped to weaken their enemy [...]" Although Sub-Saharan African ivory carvings depicting Muslim merchant caravans and a blueprint of a fast sailing vessel would support the first and second part of the argument, respectively, I believe that the first primary source would most likely support the totality of the argument, since it reflects the opinion of important European leaders—members of the Spanish royal council—concerning strategies for defeating the Muslims, and surely their increasing power, therefore supporting both parts or sections of the argument. Option B does not apply here, since the excerpt is talking about trade in Sub-Saharan Africa and Asia.
