Explanation
Correct answer: D.
Choice D is the best answer. “Consequently” logically signals that the information in this sentence—that many Arabic words entered the Spanish language—is a result or consequence of the previous information about Arabic-speaking Muslim states ruling Al-Andalus for centuries.
Why the other choices are wrong
Choice A
Choice A is incorrect because “for example” illogically signals that the information about Arabic words entering Spanish exemplifies the Arabic-speaking history of Al-Andalus mentioned in the previous sentence. Instead, Arabic words entering Spanish is a consequence of that history.
Choice B
Choice B is incorrect because “instead” illogically signals that the information about Arabic words entering Spanish provides an alternative to the Arabic-speaking history of Al-Andalus mentioned in the previous sentence. The information about Arabic words entering Spanish is a consequence of that history.
Choice C
Choice C is incorrect because “specifically” illogically signals that the information about Arabic words entering Spanish provides specific details elaborating on the Arabic-speaking history of Al-Andalus mentioned in the previous sentence. Instead, Arabic words entering Spanish is a consequence of that history.