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.

Input: Consider Input: Passage: Until the Church Building Act of 1818, the period saw relatively few churches built in Britain, which was already well-supplied, although in the later years of the period the demand for Non-conformist and Roman Catholic places of worship greatly increased. Anglican churches that were built were designed internally to allow maximum audibility, and visibility, for preaching, so the main nave was generally wider and shorter than in medieval plans, and often there were no side-aisles. Galleries were common in new churches. Especially in country parishes, the external appearance generally retained the familiar signifiers of a Gothic church, with a tower or spire, a large west front with one or more doors, and very large windows along the nave, but all with any ornament drawn from the classical vocabulary. Where funds permitted, a classical temple portico with columns and a pediment might be used at the west front. Decoration inside was very limited, but churches filled up with monuments to the prosperous.

Output: What act slowed the building of churches in Britain?

Input: Consider Input: Passage: Because of their long life, fast switching times, and their ability to be seen in broad daylight due to their high output and focus, LEDs have been used in brake lights for cars' high-mounted brake lights, trucks, and buses, and in turn signals for some time, but many vehicles now use LEDs for their rear light clusters. The use in brakes improves safety, due to a great reduction in the time needed to light fully, or faster rise time, up to 0.5 second faster[citation needed] than an incandescent bulb. This gives drivers behind more time to react. In a dual intensity circuit (rear markers and brakes) if the LEDs are not pulsed at a fast enough frequency, they can create a phantom array, where ghost images of the LED will appear if the eyes quickly scan across the array. White LED headlamps are starting to be used. Using LEDs has styling advantages because LEDs can form much thinner lights than incandescent lamps with parabolic reflectors.

Output: Why are non-LED lights sought after for various applications?

Input: Consider Input: Passage: During the 18th and 19th centuries, federal law traditionally focused on areas where there was an express grant of power to the federal government in the federal Constitution, like the military, money, foreign relations (especially international treaties), tariffs, intellectual property (specifically patents and copyrights), and mail. Since the start of the 20th century, broad interpretations of the Commerce and Spending Clauses of the Constitution have enabled federal law to expand into areas like aviation, telecommunications, railroads, pharmaceuticals, antitrust, and trademarks. In some areas, like aviation and railroads, the federal government has developed a comprehensive scheme that preempts virtually all state law, while in others, like family law, a relatively small number of federal statutes (generally covering interstate and international situations) interacts with a much larger body of state law. In areas like antitrust, trademark, and employment law, there are powerful laws at both the federal and state levels that coexist with each other. In a handful of areas like insurance, Congress has enacted laws expressly refusing to regulate them as long as the states have laws regulating them (see, e.g., the McCarran-Ferguson Act).
Output: What areas of law were generally ignored in the 18th and 19th centuries?