Great question. The question says, "Which one of the following is a principle that can be most reasonably considered to underlie the reasoning in both of the passages?"
In reading both of the passages, we see that both of them use the word "problematic" to discuss the various difficulties that the Roma face. And, because these difficulties that the Roma face exist because they're not recognized as legitimate minority groups by certain governments, then a lack of such recognition is detrimental for the Roma's interests.
In looking at the answer choices, (B) says, "A minority group’s not being officially recognized as such by the government that has jurisdiction over it can be detrimental to the group’s interests."
As mentioned above, this is a principle that we see presented in both of the passages, so (B) is our correct answer.
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