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: Menander Protector mentions a Daurentius (577–579) that slew an Avar envoy of Khagan Bayan I. The Avars asked the Slavs to accept the suzerainty of the Avars, he however declined and is reported as saying: "Others do not conquer our land, we conquer theirs – so it shall always be for us".

A: When did Protector live?
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Q: Passage: A sequel to Spectre will begin development in spring 2016. Sam Mendes has stated he will not return to direct the next 007 film. Christoph Waltz has signed on for two more films in the series, but his return depends on whether or not Craig will again portray Bond.

A: A prequel to Spectre will begin when?
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Q: Passage: The Byzantine Empire ruled the northern shores of the Sahara from the 5th to the 7th centuries. After the Muslim conquest of Arabia (Arabian peninsula) the Muslim conquest of North Africa began in the mid-7th to early 8th centuries, Islamic influence expanded rapidly on the Sahara. By the end of 641 all of Egypt was in Muslim hands. The trade across the desert intensified. A significant slave trade crossed the desert. It has been estimated that from the 10th to 19th centuries some 6,000 to 7,000 slaves were transported north each year.

A:
During what century did the Muslim conquest of Arabia begin?
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