Final answer:
Christianity in western Europe and Islam in the Middle East, before 1000 C.E., were both strongly influenced by Judaism due to their shared Abrahamic roots. They spread differently; Christianity primarily through proselytization and Islam through trade and military conquest. Both encouraged literacy to some extent, but they differed in their religious leadership structure.
Step-by-step explanation:
The main similarity between Christianity in western Europe and Islam in the Middle East before 1000 C.E. is that both were strongly influenced by Judaism (option A). Christianity and Islam are considered Abrahamic religions, meaning they trace their origins back to the prophet Abraham. They share many concepts including monotheism and the idea of a prophetic tradition.
However, they spread in different ways. While Christianity focused on proselytization and missionary work, Islam spread primarily through trade, conquest, and migration (option B). Both did encourage the spread of literacy (option C), but with different degrees of emphasis and success. For example, while the establishment of Islamic religious institutions in new communities often accompanied the spread of Arabic script and literacy, similar systematic efforts were less visible in early Christianity. Lastly, whereas Christianity was led by a hierarchical ecclesiastical structure with the pope at its head, Islam was not under one supreme religious authority (option D).
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