The Short NASDAQ-100 ProFund Service Class (SOPSX) is a mutual fund that aims to provide investors with a way to profit from a decline in the NASDAQ-100 Index. This fund uses a short selling strategy, meaning it sells borrowed shares in the index in the hopes of buying them back at a lower price in the future. This fund is designed for investors who are bearish on the performance of the NASDAQ-100 and want to hedge against potential losses in their portfolio.