This task is about writing a correct answer for the reading comprehension task. Based on the information provided in a given passage, you should identify the shortest continuous text span from the passage that serves as an answer to the given question. Avoid answers that are incorrect or provides incomplete justification for the question.

Q: Passage: Most migrations begin with the birds starting off in a broad front. Often, this front narrows into one or more preferred routes termed flyways. These routes typically follow mountain ranges or coastlines, sometimes rivers, and may take advantage of updrafts and other wind patterns or avoid geographical barriers such as large stretches of open water. The specific routes may be genetically programmed or learned to varying degrees. The routes taken on forward and return migration are often different. A common pattern in North America is clockwise migration, where birds flying North tend to be further West, and flying South tend to shift Eastwards. Question: What obsticals will migrating birds avoid?

A: large stretches of open water
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Q: Passage: Typical of Slavic languages, Czech marks its verbs for one of two grammatical aspects: perfective and imperfective. Most verbs are part of inflected aspect pairs—for example, koupit (perfective) and kupovat (imperfective). Although the verbs' meaning is similar, in perfective verbs the action is completed and in imperfective verbs it is ongoing. This is distinct from past and present tense, and any Czech verb of either aspect can be conjugated into any of its three tenses. Aspect describes the state of the action at the time specified by the tense. Question: In perfective verbs, what state is the action the verb describes in?

A: completed
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Q: Passage: Monotheists hold that there is only one god, and may claim that the one true god is worshiped in different religions under different names. The view that all theists actually worship the same god, whether they know it or not, is especially emphasized in Hinduism and Sikhism. In Christianity, the doctrine of the Trinity describes God as one God in three persons. The Trinity comprises God the Father, God the Son (Jesus), and God the Holy Spirit. Islam's most fundamental concept is tawhid (meaning "oneness" or "uniqueness"). God is described in the Quran as: "Say: He is Allah, the One and Only; Allah, the Eternal, Absolute; He begetteth not, nor is He begotten; And there is none like unto Him." Muslims repudiate the Christian doctrine of the Trinity and divinity of Jesus, comparing it to polytheism. In Islam, God is beyond all comprehension or equal and does not resemble any of his creations in any way. Thus, Muslims are not iconodules, and are not expected to visualize God. Question: What do Muslims think of Christianity?

A:
comparing it to polytheism
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