U.S. stocks extended gains to close higher for a fourth session Tuesday as investors turned defensive, snapping up consumer staples and utilities shares. Defensive stocks are favored in times of uncertainty as they are viewed as less sensitive to economic cycles. However, financial shares turned south ahead of big bank earnings later this week. The Dow Jones Industrial Average climbed 142 points, or 0.6%, to 24,919. The S&P 500 rose 9 points, or 0.4%, to 2,793 while the Nasdaq Composite Index added 3 points to 7,759.