GLOBAL MARKETS-Euro falls to 9-year low; Greece and ECB in focus

* Euro slumps to 9-year low* "Grexit" fears resurface, ECB QE eyed* Stocks volatile as oil extends lossesBy Jamie McGeeverLONDON, Jan 5 (Reuters) - The euro slumped to a nine-year low on Monday as investors bet that the prospect of inflation across the region turning negative and mounting political uncertainty in Greece will force the European Central Bank to unleash quantitative easing.European s