(Reuters) – A slumping housing market and geopolitical tensions risk undermining the U.S. economy and bear close watching by the Federal Reserve, the central bank’s chief said on Wednesday. In testimony to Congress, Fed Chair Janet Yellen repeated her stance that the economy was still in need of lots of support given the “considerable slack” in the labor market. While she offered few new clues on the direction of interest rates, Yellen broke ground in […]