Snapping a two-day rally, the Sensex at the Bombay Stock Exchange dropped 213 points, or 1.3 percent, to 16,285, on Wednesday, on profit-booking by investors, amid falling Asian markets. The Nifty lost 60 points, or 1.2 percent, to 4,889.Stock markets in Japan, China, Hong Kong, South Korea and Singapore dropped between 0.5 percent and 2 percent, after credit rating agency, Moody's downgraded Japan's sovereign debt rating.