Generate a correct and concise answer for the question based on the words in the context.

Q: Context : Charlie Brooker's Screenwipe is a British television review programme created and presented by Charlie Brooker and broadcast on BBC Four. 
Question : What channel aired Charlie Brooker's Screenwipe?

A: BBC Four
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Q: Context : Sofia Maria Ekwall, (1826--1897), was a Swedish woman judged for two murders and for the murder of her father. 
Question : Which crime led to the conviction of Sofia Maria Ekwall?

A: murder
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Q: Context : Fields of Sacrifice was produced by the National Film Board of Canada (NFB) for the Canadian Department of Veteran Affairs. 
Question : What studio produced Fields of Sacrifice?

A:
National Film Board of Canada
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