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: Contract law covers obligations established by agreement (express or implied) between private parties. Generally, contract law in transactions involving the sale of goods has become highly standardized nationwide as a result of the widespread adoption of the Uniform Commercial Code. However, there is still significant diversity in the interpretation of other kinds of contracts, depending upon the extent to which a given state has codified its common law of contracts or adopted portions of the Restatement (Second) of Contracts.
[A]: What does contract law not cover?

[Q]: Passage: Another milestone in the early development of Baptist doctrine was in 1638 with John Spilsbury, a Calvinistic minister who helped to promote the strict practice of believer's baptism by immersion. According to Tom Nettles, professor of historical theology at Southern Baptist Theological Seminary, "Spilsbury's cogent arguments for a gathered, disciplined congregation of believers baptized by immersion as constituting the New Testament church gave expression to and built on insights that had emerged within separatism, advanced in the life of John Smyth and the suffering congregation of Thomas Helwys, and matured in Particular Baptists."
[A]: When did John Spilsbury create the strict practice of immersion?

[Q]: Passage: On 20 February 2001, the bureau announced that a special agent, Robert Hanssen (born 1944) had been arrested for spying for the Soviet Union and then Russia from 1979 to 2001. He is serving 15 consecutive life sentences without the possibility of parole at ADX Florence, a federal supermax prison near Florence, Colorado. Hanssen was arrested on February 18, 2001 at Foxstone Park near his home in Vienna, Virginia, and was charged with selling US secrets to the USSR and subsequently Russia for more than US$1.4 million in cash and diamonds over a 22-year period. On July 6, 2001, he pleaded guilty to 15 counts of espionage in the United States District Court for the Eastern District of Virginia. His spying activities have been described by the US Department of Justice's Commission for the Review of FBI Security Programs as "possibly the worst intelligence disaster in U.S. history".
[A]:
Who had spied for the Soviet Union before 1979?