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.

[EX Q]: Passage: Since World War II, aircraft carrier designs have increased in size to accommodate a steady increase in aircraft size. The large, modern Nimitz class of US carriers has a displacement nearly four times that of the World War II–era USS Enterprise, yet its complement of aircraft is roughly the same—a consequence of the steadily increasing size and weight of military aircraft over the years. Today's aircraft carriers are so expensive that nations which operate them risk significant political, economic, and military impact if a carrier is lost, or even used in conflict.
[EX A]: Why have aircraft carriers increased in size since World War I?

[EX Q]: Passage: The meaning of federalism, as a political movement, and of what constitutes a 'federalist', varies with country and historical context.[citation needed] Movements associated with the establishment or development of federations can exhibit either centralising or decentralising trends.[citation needed] For example, at the time those nations were being established, factions known as "federalists" in the United States and Australia advocated the formation of strong central government. Similarly, in European Union politics, federalists mostly seek greater EU integration. In contrast, in Spain and in post-war Germany, federal movements have sought decentralisation: the transfer of power from central authorities to local units. In Canada, where Quebec separatism has been a political force for several decades, the "federalist" impulse aims to keep Quebec inside Canada.
[EX A]: What isn't the meaning of federalism?

[EX Q]: Passage: Under the Bretton Woods system established after World War II, the value of gold was fixed to $35 per ounce, and the value of the U.S. dollar was thus anchored to the value of gold. Rising government spending in the 1960s, however, led to doubts about the ability of the United States to maintain this convertibility, gold stocks dwindled as banks and international investors began to convert dollars to gold, and as a result the value of the dollar began to decline. Facing an emerging currency crisis and the imminent danger that the United States would no longer be able to redeem dollars for gold, gold convertibility was finally terminated in 1971 by President Nixon, resulting in the "Nixon shock".
[EX A]:
When was the Nixon Woods system established?