The Nuveen S&P 500 Buy-Write Income Fund of Benef Interest (BXMX) is a mutual fund that seeks to provide investors with income and capital appreciation by investing in a portfolio of stocks from the S&P 500 index and writing covered call options on those stocks. This strategy allows the fund to generate additional income while potentially reducing volatility. The fund is managed by Nuveen, a leading global investment firm, and is suitable for investors seeking a diversified approach to investing in large-cap stocks with an added income component.