Extract the answer to the question from the following context. Question: What study focuses on Jesus? Context: Mary's complete sinlessness and concomitant exemption from any taint from the first moment of her existence was a doctrine familiar to Greek theologians of Byzantium. Beginning with St. Gregory Nazianzen, his explanation of the "purification" of Jesus and Mary at the circumcision (Luke 2:22) prompted him to consider the primary meaning of "purification" in Christology (and by extension in Mariology) to refer to a perfectly sinless nature that manifested itself in glory in a moment of grace (e.g., Jesus at his Baptism). St. Gregory Nazianzen designated Mary as "prokathartheisa (prepurified)." Gregory likely attempted to solve the riddle of the Purification of Jesus and Mary in the Temple through considering the human natures of Jesus and Mary as equally holy and therefore both purified in this manner of grace and glory. Gregory's doctrines surrounding Mary's purification were likely related to the burgeoning commemoration of the Mother of God in and around Constantinople very close to the date of Christmas. Nazianzen's title of Mary at the Annunciation as "prepurified" was subsequently adopted by all theologians interested in his Mariology to justify the Byzantine equivalent of the Immaculate Conception. This is especially apparent in the Fathers St. Sophronios of Jerusalem and St. John Damascene, who will be treated below in this article at the section on Church Fathers. About the time of Damascene, the public celebration of the "Conception of St. Ann [i.e., of the Theotokos in her womb]" was becoming popular. After this period, the "purification" of the perfect natures of Jesus and Mary would not only mean moments of grace and glory at the Incarnation and Baptism and other public Byzantine liturgical feasts, but purification was eventually associated with the feast of Mary's very conception (along with her Presentation in the Temple as a toddler) by Orthodox authors of the 2nd millennium (e.g., St. Nicholas Cabasilas and Joseph Bryennius).
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Answer: Christology

Extract the answer to the question from the following context. Question: In 2001, __ was blocked by a sandbar. Context: During the American occupation of the state, the number of Indian attacks was drastically reduced, but in 1848 the attacks resumed to such a degree that the Mexican officials had no choice but to resume military projects to protect Mexican settlements in the state. Through the next three decades the state faced constant attacks from indigenous on Mexican settlements. After the occupation the people of the state were worried about the potential attack from the hostile indigenous tribes north of the Rio Grande; as a result a decree on July 19, 1848, the state established 18 military colonies along the Rio Grande. The new military colonies were to replace the presidios as population centers to prevent future invasions by indigenous tribes; these policies remained prominent in the state until 1883. Eventually the state replaced the old state security with a state policy to form militias organized with every Mexican in the state capable to serve between the ages of 18 and 55 to fulfill the mandate of having six men defending for every 1000 residents.
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Answer: Rio Grande

Extract the answer to the question from the following context. Question: What is an island in the Aegean beginning with the letter K? Context: The Pindus range continues through the central Peloponnese, crosses the islands of Kythera and Antikythera and finds its way into southwestern Aegean, in the island of Crete where it eventually ends. The islands of the Aegean are peaks of underwater mountains that once constituted an extension of the mainland. Pindus is characterized by its high, steep peaks, often dissected by numerous canyons and a variety of other karstic landscapes. The spectacular Vikos Gorge, part of the Vikos-Aoos National Park in the Pindus range, is listed by the Guinness book of World Records as the deepest gorge in the world. Another notable formation are the Meteora rock pillars, atop which have been built medieval Greek Orthodox monasteries.
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Answer:
Kythera