In this task, you are given a question and a context passage. You have to answer the question based on the given passage.
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Question: The expansion of what further cemented Houston's emergence as a powerhouse commercial city?, Context: By 1860, Houston had emerged as a commercial and railroad hub for the export of cotton. Railroad spurs from the Texas inland converged in Houston, where they met rail lines to the ports of Galveston and Beaumont. During the American Civil War, Houston served as a headquarters for General John Bankhead Magruder, who used the city as an organization point for the Battle of Galveston. After the Civil War, Houston businessmen initiated efforts to widen the city's extensive system of bayous so the city could accept more commerce between downtown and the nearby port of Galveston. By 1890, Houston was the railroad center of Texas.

Answer: bayous


Question: Of the potential effects on Russia that resulted in large-scale population losses, which one would be considered out of the nation's control?, Context: The first half of the 20th century in Russia and the Soviet Union was marked by a succession of wars, famines and other disasters, each accompanied by large-scale population losses. Stephen J. Lee estimates that, by the end of World War II in 1945, the Russian population was about 90 million fewer than it could have been otherwise.

Answer: disasters


Question: What is the relation of a critical edition to an original text?, Context: When comparing different documents, or "witnesses", of a single, original text, the observed differences are called variant readings, or simply variants or readings. It is not always apparent which single variant represents the author's original work. The process of textual criticism seeks to explain how each variant may have entered the text, either by accident (duplication or omission) or intention (harmonization or censorship), as scribes or supervisors transmitted the original author's text by copying it. The textual critic's task, therefore, is to sort through the variants, eliminating those most likely to be un-original, hence establishing a "critical text", or critical edition, that is intended to best approximate the original. At the same time, the critical text should document variant readings, so the relation of extant witnesses to the reconstructed original is apparent to a reader of the critical edition. In establishing the critical text, the textual critic considers both "external" evidence (the age, provenance, and affiliation of each witness) and "internal" or "physical" considerations (what the author and scribes, or printers, were likely to have done).

Answer:
is intended to best approximate the original