Problem: Given the question: Extract the answer to the question from the following context. Question: Some eggs stay? Context: However, the lifecycles of most living polychaetes, which are almost all marine animals, are unknown, and only about 25% of the 300+ species whose lifecycles are known follow this pattern. About 14% use a similar external fertilization but produce yolk-rich eggs, which reduce the time the larva needs to spend among the plankton, or eggs from which miniature adults emerge rather than larvae. The rest care for the fertilized eggs until they hatch some by producing jelly-covered masses of eggs which they tend, some by attaching the eggs to their bodies and a few species by keeping the eggs within their bodies until they hatch. These species use a variety of methods for sperm transfer; for example, in some the females collect sperm released into the water, while in others the males have a penis that inject sperm into the female. There is no guarantee that this is a representative sample of polychaetes' reproductive patterns, and it simply reflects scientists' current knowledge.
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The answer is:
within their bodies until they hatch

Problem: Given the question: Extract the answer to the question from the following context. Question: Who wanted access to a white fluffy plant? Context: Russian Imperialism led to the Russian Empire's conquest of Central Asia during the late 19th century's Imperial Era. Between 1864 and 1885 Russia gradually took control of the entire territory of Russian Turkestan, the Tajikistan portion of which had been controlled by the Emirate of Bukhara and Khanate of Kokand. Russia was interested in gaining access to a supply of cotton and in the 1870s attempted to switch cultivation in the region from grain to cotton (a strategy later copied and expanded by the Soviets).[citation needed] By 1885 Tajikistan's territory was either ruled by the Russian Empire or its vassal state, the Emirate of Bukhara, nevertheless Tajiks felt little Russian influence.[citation needed]
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The answer is:
Russia

Problem: Given the question: Extract the answer to the question from the following context. Question: What new early text raises questions about an ancient work's original sourcing? Context: Many ancient works, such as the Bible and the Greek tragedies,[citation needed] survive in hundreds of copies, and the relationship of each copy to the original may be unclear. Textual scholars have debated for centuries which sources are most closely derived from the original, hence which readings in those sources are correct.[citation needed] Although biblical books that are letters, like Greek plays, presumably had one original, the question of whether some biblical books, like the Gospels, ever had just one original has been discussed. Interest in applying textual criticism to the Qur'an has also developed after the discovery of the Sana'a manuscripts in 1972, which possibly date back to the 78th centuries.
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The answer is:
Sana'a manuscripts