This task is about creating an unanswerable question based on a given passage. Construct a question that looks relevant to the given context but is unanswerable. Following are a few suggestions about how to create unanswerable questions:
(i) create questions which require satisfying a constraint that is not mentioned in the passage
(ii) create questions which require information beyond what is provided in the passage in order to answer
(iii) replace an existing entity, number, date mentioned in the passage with other entity, number, date and use it in the question
(iv) create a question which is answerable from the passage and then replace one or two words by their antonyms or insert/remove negation words to make it unanswerable.
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Question: Passage: In the former Soviet Union, electric traction eventually became somewhat more energy-efficient than diesel. Partly due to inefficient generation of electricity in the USSR (only 20.8% thermal efficiency in 1950 vs. 36.2% in 1975), in 1950 diesel traction was about twice as energy efficient as electric traction (in terms of net tonne-km of freight per kg of fuel). But as efficiency of electricity generation (and thus of electric traction) improved, by about 1965 electric railways became more efficient than diesel. After the mid 1970s electrics used about 25% less fuel per ton-km. However diesels were mainly used on single track lines with a fair amount of traffic  so that the lower fuel consumption of electrics may be in part due to better operating conditions on electrified lines (such as double tracking) rather than inherent energy efficiency. Nevertheless, the cost of diesel fuel was about 1.5 times more (per unit of heat energy content) than that of the fuel used in electric power plants (that generated electricity), thus making electric railways even more energy-cost effective.

Answer: In the US, electric traction became more energy-efficient than what?


Question: Passage: The origins of the Samoans are closely studied in modern research about Polynesia in various scientific disciplines such as genetics, linguistics and anthropology. Scientific research is ongoing, although a number of different theories exist; including one proposing that the Samoans originated from Austronesian predecessors during the terminal eastward Lapita expansion period from Southeast Asia and Melanesia between 2,500 and 1,500 BCE. The Samoan origins are currently being reassessed due to new scientific evidence and carbon dating findings from 2003 and onwards.

Answer: What scientific disciplines are being used to study where the Austronesian people came from?


Question: Passage: The term "Gothic architecture" originated as a pejorative description. Giorgio Vasari used the term "barbarous German style" in his Lives of the Artists to describe what is now considered the Gothic style, and in the introduction to the Lives he attributes various architectural features to "the Goths" whom he holds responsible for destroying the ancient buildings after they conquered Rome, and erecting new ones in this style. At the time in which Vasari was writing, Italy had experienced a century of building in the Classical architectural vocabulary revived in the Renaissance and seen as evidence of a new Golden Age of learning and refinement.

Answer:
What type of description did the term "Gothic architecture" dismiss?