2. Speaking at the annual shareholders' meeting of 2020, Mr. Buffett said "the world has changed" because of the coronavirus. He then said he had been wrong to invest in the airline industry. The conglomerate had an 11% stake in Delta Air Lines, 10% of American Airlines, 10% of Southwest Airlines, and 9% of United Airlines, according to its annual report and company filings. Warren Buffett says his company Berkshire Hathaway has sold all of its shares in the four largest US airlines. Which one of the following provides the most efficient means for Mr. Warren Buffett to sell his shares? A. Secondary market transaction Proxy statement C. Private placement transaction D. Stakeholder purchase E. Issuer-sponsored Dutch auction B