In this task, you are given a question and a context passage. You have to answer the question based on the given passage.

Example Input: What did his thinking conflict with?, Context: In the early 11th century, the Muslim physicist Ibn al-Haytham (Alhacen or Alhazen) discussed space perception and its epistemological implications in his Book of Optics (1021), he also rejected Aristotle's definition of topos (Physics IV) by way of geometric demonstrations and defined place as a mathematical spatial extension. His experimental proof of the intromission model of vision led to changes in the understanding of the visual perception of space, contrary to the previous emission theory of vision supported by Euclid and Ptolemy. In "tying the visual perception of space to prior bodily experience, Alhacen unequivocally rejected the intuitiveness of spatial perception and, therefore, the autonomy of vision. Without tangible notions of distance and size for correlation, sight can tell us next to nothing about such things."
Example Output: Aristotle's definition of topos

Example Input: The Russian Federation was?, Context: On December 25, 1991, following the collapse of the Soviet Union, the republic was renamed the Russian Federation, which it remains to this day. This name and "Russia" were specified as the official state names in the April 21, 1992 amendment to the existing constitution and were retained as such in the 1993 Constitution of Russia.
Example Output: Soviet Union

Example Input: What are a capella singers known to do with their voices?, Context: In addition to singing words, some a cappella singers also emulate instrumentation by reproducing instrumental sounds with their vocal cords and mouth. One of the earliest 20th century practitioners of this method were The Mills Brothers whose early recordings of the 1930s clearly stated on the label that all instrumentation was done vocally. More recently, "Twilight Zone" by 2 Unlimited was sung a cappella to the instrumentation on the comedy television series Tompkins Square. Another famous example of emulating instrumentation instead of singing the words is the theme song for The New Addams Family series on Fox Family Channel (now ABC Family). Groups such as Vocal Sampling and Undivided emulate Latin rhythms a cappella. In the 1960s, the Swingle Singers used their voices to emulate musical instruments to Baroque and Classical music. Vocal artist Bobby McFerrin is famous for his instrumental emulation. A cappella group Naturally Seven recreates entire songs using vocal tones for every instrument.
Example Output:
In addition to singing words, some a cappella singers also emulate instrumentation by reproducing instrumental sounds with their vocal cords and mouth