George Soros earned the nickname "The Man Who Broke the Bank of England" after his hedge fund, Quantum Fund, made a massive bet against the British pound in September 1992. On what became known as Black Wednesday, 16 September 1992, the United Kingdom was forced to withdraw the pound from the European Exchange Rate Mechanism after failing to keep the currency above its agreed lower limit despite raising interest rates sharply. Soros's fund had built a huge short position against the pound, and when the currency collapsed, his fund reportedly profited by around $1 billion, cementing his fame as a currency speculator.
George W Bush was a US president with no role in this currency event. Paul Volcker was a former chairman of the US Federal Reserve known for fighting inflation in the early 1980s, not for currency speculation against the pound. Ben Bernanke was Federal Reserve chairman during the 2008 financial crisis, also unconnected to the 1992 pound crisis. None of these three had any part in the Black Wednesday trade, which makes George Soros the only correct answer.