What is the likeliest explanation for why the arrival in Argentina of the Covid-19 pandemic resulted in an increase in the country's monetary base? A. Its central bank was likely selling large amounts of government securities, causing its balance sheet to shrink. B. The central bank had likely decreased the money supply to stabilize the economy, causing the monetary base to increase. C. Its central bank was likely purchasing large amounts of government securities, causing its balance sheet to expand. D. The government had likely decreased its fiscal spending to stabilize the economy, causing the monetary base to increase