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.

[Q]: Passage: Infrared reflectography (fr; it; es), as called by art conservators, can be applied to paintings to reveal underlying layers in a completely non-destructive manner, in particular the underdrawing or outline drawn by the artist as a guide. This often reveals the artist's use of carbon black, which shows up well in reflectograms, as long as it has not also been used in the ground underlying the whole painting. Art conservators are looking to see whether the visible layers of paint differ from the underdrawing or layers in between – such alterations are called pentimenti when made by the original artist. This is very useful information in deciding whether a painting is the prime version by the original artist or a copy, and whether it has been altered by over-enthusiastic restoration work. In general, the more pentimenti the more likely a painting is to be the prime version. It also gives useful insights into working practices.
[A]: What painting technique is used to reveal working practices?


[Q]: Passage: Basic sanitation techniques can have a profound effect on the transmission of diarrheal disease. The implementation of hand washing using soap and water, for example, has been experimentally shown to reduce the incidence of disease by approximately 42–48%. Hand washing in developing countries, however, is compromised by poverty as acknowledged by the CDC: "Handwashing is integral to disease prevention in all parts of the world; however, access to soap and water is limited in a number of less developed countries. This lack of access is one of many challenges to proper hygiene in less developed countries." Solutions to this barrier require the implementation of educational programs that encourage sanitary behaviours.
[A]: What has a profound effect in developed countries?


[Q]: Passage: By July 1944, the Red Army was deep into Polish territory and pursuing the Germans toward Warsaw. Knowing that Stalin was hostile to the idea of an independent Poland, the Polish government-in-exile in London gave orders to the underground Home Army (AK) to try to seize control of Warsaw from the Germans before the Red Army arrived. Thus, on 1 August 1944, as the Red Army was nearing the city, the Warsaw Uprising began. The armed struggle, planned to last 48 hours, was partially successful, however it went on for 63 days. Eventually the Home Army fighters and civilians assisting them were forced to capitulate. They were transported to PoW camps in Germany, while the entire civilian population was expelled. Polish civilian deaths are estimated at between 150,000 and 200,000.
[A]:
What army was pushing deep into Polish territory to pursue The Home Army fighters in 1944?