The Bombay Stock Exchange benchmark Sensex on Monday fell by over 175 points, in early trade on fresh spell of selling by funds.The 30-share Sensex fell by 175.85 points to 16,182.11 points in early trade. The wide-based National Stock Exchange index Nifty declined by 50.50 points, to 4,831.55 points. Broker's said sentiments on the domestic bourses were dampened by weak trend in global markets, triggering selling by funds as well as retail investors.