Question: Extract the answer to the question from the following context. Question: What word is in quotations the most? Context: A elevator of this kind uses a vacuum on top of the cab and a valve on the top of the "shaft" to move the cab upwards and closes the valve in order to keep the cab at the same level. a diaphragm or a piston is used as a "brake" if there's a sudden increase in pressure avove the cab. however, to go down, it opens the valve so that the air can pressurize the top of the "shaft", allowing the cab to go down by its own weight. this also means that in case of a power failure, the cab will automatically go down. the "shaft" is made of acrilic, is always round, due to the shape of the vacuum pump turbine. in order to keep the air inside of the cab, rubber seals are used. due to technical limitations, these elevators have a low capacity. they usually allow 1-3 passengers and up to 525 lbs.
Answer: shaft

Question: Extract the answer to the question from the following context. Question: the opposite of zinc deficiency in plants is what Context: Zinc deficiency is crop plants' most common micronutrient deficiency; it is particularly common in high-pH soils. Zinc-deficient soil is cultivated in the cropland of about half of Turkey and India, a third of China, and most of Western Australia, and substantial responses to zinc fertilization have been reported in these areas. Plants that grow in soils that are zinc-deficient are more susceptible to disease. Zinc is primarily added to the soil through the weathering of rocks, but humans have added zinc through fossil fuel combustion, mine waste, phosphate fertilizers, pesticide (zinc phosphide), limestone, manure, sewage sludge, and particles from galvanized surfaces. Excess zinc is toxic to plants, although zinc toxicity is far less widespread.
Answer: Excess zinc

Question: Extract the answer to the question from the following context. Question: __ has never won a seat on Congress. Context: The United States has become essentially a two-party system. Since a conservative (such as the Republican Party) and liberal (such as the Democratic Party) party has usually been the status quo within American politics. The first parties were called Federalist and Republican, followed by a brief period of Republican dominance before a split occurred between National Republicans and Democratic Republicans. The former became the Whig Party and the latter became the Democratic Party. The Whigs survived only for two decades before they split over the spread of slavery, those opposed becoming members of the new Republican Party, as did anti-slavery members of the Democratic Party. Third parties (such as the Libertarian Party) often receive little support and are very rarely the victors in elections. Despite this, there have been several examples of third parties siphoning votes from major parties that were expected to win (such as Theodore Roosevelt in the election of 1912 and George Wallace in the election of 1968). As third party movements have learned, the Electoral College's requirement of a nationally distributed majority makes it difficult for third parties to succeed. Thus, such parties rarely win many electoral votes, although their popular support within a state may tip it toward one party or the other. Wallace had weak support outside the South. More generally, parties with a broad base of support across regions or among economic and other interest groups, have a great chance of winning the necessary plurality in the U.S.'s largely single-member district, winner-take-all elections. The tremendous land area and large population of the country are formidable challenges to political parties with a narrow appeal.
Answer:
Libertarian