You will be given a definition of a task first, then an example. Follow the example to solve a new instance of the task.
Use a disfluent question or a proper question and find the answer to the question based on the given context or return None if an answer can't be found. A disfluent question is a question that has some interruptions in it while framing. A proper question is the correct form of the question without any disfluency.

proper question: In what year did the U of C become one of 7 founding members of the Association of Chicago Universities?
disfluent question: In what year did Robert Harper or did the U of C become one of 7 founding members of the Association of Chicago Universities?
context: Founded by the American Baptist Education Society with a donation from oil magnate and wealthiest man in history John D. Rockefeller, the University of Chicago was incorporated in 1890; William Rainey Harper became the university's first president in 1891, and the first classes were held in 1892. Both Harper and future president Robert Maynard Hutchins advocated for Chicago's curriculum to be based upon theoretical and perennial issues rather than on applied sciences and commercial utility. With Harper's vision in mind, the University of Chicago also became one of the 14 founding members of the Association of American Universities, an international organization of leading research universities, in 1900.
Solution: None
Why? The answer to the above question is not found from the context hence it is not answerable so the output is 'None' so it is a positive example.

New input: proper question: What were the Saxon Palace and Bruhl Palace in prewar Warsaw?
disfluent question: What building no sorry What were the Saxon Palace and Bruhl Palace in prewar Warsaw?
context: Exceptional examples of the bourgeois architecture of the later periods were not restored by the communist authorities after the war (like mentioned Kronenberg Palace and Insurance Company Rosja building) or they were rebuilt in socialist realism style (like Warsaw Philharmony edifice originally inspired by Palais Garnier in Paris). Despite that the Warsaw University of Technology building (18991902) is the most interesting of the late 19th-century architecture. Some 19th-century buildings in the Praga district (the Vistula's right bank) have been restored although many have been poorly maintained. Warsaw's municipal government authorities have decided to rebuild the Saxon Palace and the Bruhl Palace, the most distinctive buildings in prewar Warsaw.
Solution:
most distinctive buildings