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: The most precise timekeeping device of the ancient world was the water clock, or clepsydra, one of which was found in the tomb of Egyptian pharaoh Amenhotep I (1525–1504 BC). They could be used to measure the hours even at night, but required manual upkeep to replenish the flow of water. The Ancient Greeks and the people from Chaldea (southeastern Mesopotamia) regularly maintained timekeeping records as an essential part of their astronomical observations. Arab inventors and engineers in particular made improvements on the use of water clocks up to the Middle Ages. In the 11th century, Chinese inventors and engineers invented the first mechanical clocks driven by an escapement mechanism.

SOLUTION: What device was invented by the ancient Greeks?

PROBLEM: Passage: Proponents of affirmative action recognize that the policy is inherently unequal; however, minding the inescapable fact that historic inequalities exist in America, they believe the policy is much more fair than one in which these circumstances are not taken into account. Furthermore, those in favor of affirmative action see it as an effort towards inclusion rather than a discriminatory practice. "Job discrimination is grounded in prejudice and exclusion, whereas affirmative action is an effort to overcome prejudicial treatment through inclusion. The most effective way to cure society of exclusionary practices is to make special efforts at inclusion, which is exactly what affirmative action does."

SOLUTION: What is one of the issues with non-affirmative action?

PROBLEM: Passage: Some software assigned special meanings to ASCII characters sent to the software from the terminal. Operating systems from Digital Equipment Corporation, for example, interpreted DEL as an input character as meaning "remove previously-typed input character", and this interpretation also became common in Unix systems. Most other systems used BS for that meaning and used DEL to mean "remove the character at the cursor".[citation needed] That latter interpretation is the most common now.[citation needed]

SOLUTION:
What did some software do to the Digital Equipment Corporation?