TASK DEFINITION: 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: One way to divide hunter-gatherer groups is by their return systems. James Woodburn uses the categories "immediate return" hunter-gatherers for egalitarian and "delayed return" for nonegalitarian. Immediate return foragers consume their food within a day or two after they procure it. Delayed return foragers store the surplus food (Kelly, 31).

SOLUTION: What is the only way to divide hunter-gatherer groups?

PROBLEM: Passage: CBC Television stations can be received in many United States communities along the Canadian border over-the-air and have a significant audience in those areas. Such a phenomenon can also take place within Great Lakes communities such as Ashtabula, Ohio, which received programming from the CBC's London, Ontario, transmitter, based upon prevailing atmospheric conditions over Lake Erie. As of September 2010 CBC shut down its analogue transmitter and decided not to replace it with a digital transmitter. As a result, there is now a giant hole in the coverage of CBC in South-Western Ontario. Both CBC - Toronto and CBC - Windsor are both over 100 miles from London, ON and out of range for even the largest antennas[citation needed].

SOLUTION: What location in the United States has the highest viewership of CBC programming?

PROBLEM: Passage: At the start of the war, no French regular army troops were stationed in North America, and few British troops. New France was defended by about 3,000 troupes de la marine, companies of colonial regulars (some of whom had significant woodland combat experience). The colonial government recruited militia support when needed. Most British colonies mustered local militia companies, generally ill trained and available only for short periods, to deal with native threats, but did not have any standing forces.

SOLUTION:
What was French military presence at end of war?