U.S. stocks were sold off Wednesday in a sign that investors are still fretting over low oil prices and are jittery after watching markets get off to a tumultuous start this year. The Dow Jones industrial average fell 364.81 points, or 2.2 percent, to 16,151.41. The Standard & Poor’s 500-stock index closed down 2.5 percent for the day, officially entering correction territory, which is defined as being off more than 10 percent from the most recent high. The tech-heavy Nasdaq composite index ended the day down 3.4 percent. The Dow and the S&P 500 are now down more than 7 percent this year, both having their worst eight-day start to a year.