Detailed Instructions: 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.
Problem:Passage: Louis' advisors believed that, as long as Strasbourg remained independent, it would endanger the King's newly annexed territories in Alsace, and, that to defend these large rural lands effectively, a garrison had to be placed in towns such as Strasbourg. Indeed, the bridge over the Rhine at Strasbourg had been used repeatedly by Imperial (Holy Roman Empire) forces, and three times during the Franco-Dutch War Strasbourg had served as a gateway for Imperial invasions into Alsace. In September 1681 Louis' forces, though lacking a clear casus belli, surrounded the city with overwhelming force. After some negotiation, Louis marched into the city unopposed on 30 September 1681 and proclaimed its annexation.
Solution:
In what year did King Louis annex Alsace?