In this task, you're given a context, further information available on a particular linked term from the statement, and an answer term. Your job is to generate a question that can use the information provided to obtain the given answer. You should use the information on both context and link information to create the question. Note that the answer to the question should be exactly the given answer, and if the answer is none, the answer to the question shouldn't be obtainable from the context or linked information.
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Question: Context: At the start of the Second World War before the US entered the war, there were a large number of American volunteers offering their services. No. 71 was formed at RAF Church Fenton on 19 September 1940 with Brewster Buffalos Link Information: Royal Air Force Church Fenton or RAF Church Fenton was a former Royal Air Force (RAF) station located south east of Tadcaster, North Yorkshire, England Answer: England

Answer: In what country was No. 71 formed?


Question: Context: Davis sailed for San Francisco, California, around Cape Horn in 1852 Link Information:  By 1890, San Francisco's population approached 300,000 Answer: approached 300,000

Answer: How many people lived in San Francisco the year Davis embarked on his journey to the city?


Question: Context: His grandfather was Admiral Link Information: Admiral Sir Reginald Neville Custance, (20 September 1847 – 30 August 1935) was a Royal Navy officer. He was the eldest son of General William Neville Custance CB. Answer: William Neville Custance

Answer:
What was the name of Wilfred's paternal great grandfather?