The Fund seeks to track the investment results of the BlackRock High Yield Defensive Bond Index (the Underlying Index), which consists of U.S. dollar-denominated, high yield (as determined by BlackRock Index Services, LLC (the Index Provider)) corporate bonds. Component securities include publicly-issued debt of U.S. corporate issuers, U.S. dollar-denominated, publicly issued debt of non-U.S. corporate issuers, and bonds offered pursuant to Rule 144A under the Securities Act of 1933, as amended (the 1933 Act) with or without registration rights. As of February 28, 2023, a significant portion of the Underlying Index is represented by securities of companies in the energy sector or industry. The components of the Underlying Index are likely to change over time.