The Fidelity Freedom 2055 Fund: Class K (FNSDX) is a mutual fund that aims to provide long-term growth and capital appreciation for investors who plan to retire in the year 2055. This fund is managed by Fidelity Investments and primarily invests in a mix of stocks and bonds, with a focus on growth-oriented investments. The Class K shares of this fund have a lower expense ratio compared to other share classes, making it a cost-effective option for investors. With a target date of 2055, this fund is designed to gradually shift towards more conservative investments as the retirement date approaches.