Strategy. The Fund seeks to track the investment results of the Bloomberg MSCI US High Yield Choice ESG Screened Index (the Underlying Index ), developed by Bloomberg Finance L.P. and its affiliates (the Index Provider or Bloomberg ) with environmental, social and governance ( ESG ) rating inputs from MSCI Solutions LLC ( MSCI Solutions ) pursuant to an agreement between MSCI Solutions and Bloomberg Index Services Limited (a subsidiary of Bloomberg) or an affiliate. The Underlying Index is a modified market value-weighted index with a cap on each issuer of 2% at each monthly rebalancing. The Underlying Index is designed to reflect the performance of U.S. dollar-denominated, high yield corporate bonds of issuers with favorable ESG ratings, as identified by … Show more… The Fund seeks to track the investment results of the Bloomberg MSCI US High Yield Choice ESG Screened Index (the Underlying Index ), developed by Bloomberg Finance L.P. and its affiliates (the Index Provider or Bloomberg ) with environmental, social and governance ( ESG ) rating inputs from MSCI Solutions LLC ( MSCI Solutions ) pursuant to an agreement between MSCI Solutions and Bloomberg Index Services Limited (a subsidiary of Bloomberg) or an affiliate. The Underlying Index is a modified market value-weighted index with a cap on each issuer of 2% at each monthly rebalancing. The Underlying Index is designed to reflect the performance of U.S. dollar-denominated, high yield corporate bonds of issuers with favorable ESG ratings, as identified by the Index Provider, while applying additional screens. To construct the Underlying Index, Bloomberg begins with the Bloomberg US Corporate High Yield Index (the Parent Index ). The Parent Index includes U.S. dollar-denominated, high yield, fixed-rate corporate bonds that: (i) are issued by companies with a developed markets country of risk, as defined by the Index Provider based primarily on quantitative economic criteria established by the Index Provider, and (ii) have a rating of below-investment grade (as determined by the Index Provider). From the Parent Index, Bloomberg selects bonds that have $400 million or more of outstanding face value at the time of inclusion. The Parent Index includes bonds with at least one year until final maturity. In determining whether a bond has a rating of below investment grade, ratings from Moodys Investors Services, Inc. ( Moodys ), Standard & Poors Global Ratings, a subsidiary of S&P Global ( S&P Global Ratings ) and Fitch Ratings, Inc. ( Fitch ) are considered. Securities in the Underlying Index must be rated high yield (below BBB- by S&P Global Ratings and Fitch, or below Baa3 by Moody's) using the middle rating from Moodys, S&P Global Ratings, and Fitch. When a rating from only two agencies is available, the lower of the two agencies ratings is used. When a rating from only one agency is available, that rating is used to determine eligibility in the Underlying Index. Securities that are rated below investment grade are commonly referred to as junk bonds. To select favorable ESG rated companies from the Parent Index, MSCI excludes companies with an ESG controversy score of less than three (3) or an ESG rating below BB. To determine if companies are involved in ESG business controversies, MSCI assesses the possible negative environmental, social, and/or governance impact of a companys operations or products on a scale from zero to ten, with zero being the most severe controversy rating. To determine ESG ratings, MSCI rates the ESG characteristics of securities on a scale of CCC (lowest) to AAA (highest). MSCI then evaluates a companys risks and opportunities using a sector-specific ESG Key Issues ( Key Issues ) ( e.g. , carbon emissions) selection and weighting model. Each company is scored on a scale of 0 to 10, with 10 being the highest, for each Key Issue before being provided an ESG rating based on average Key Issue score. MSCI Solutions also excludes securities of companies involved in adult entertainment, alcohol, gambling, tobacco, genetically modified organisms, controversial weapons, nuclear weapons, civilian firearms, conventional weapons, palm oil, for-profit prisons, predatory lending, and nuclear power based on revenue or percentage of revenue thresholds for certain categories ( e.g ., $500 million or 50%) and categorical exclusions for others ( e.g., nuclear weapons). MSCI Solutions screens companies with involvement in fossil fuels by excluding the securities of any company in the Bloomberg Class 3 energy sector ( i.e. , corporate issuers in the energy sector include both independent and integrated exploration and production companies, as well as midstream oil field services, and refining companies) and all companies with an industry tie to fossil fuels such as thermal coal, oil and gasin particular, reserve ownership, related revenues and power generation. The Underlying Index is rebalanced on a monthly basis, on the last business day of each month. As of October 31, 2025, a significant portion of the Underlying Index is represented by securities of companies in the communications, consumer goods and services and industrials industries or sectors. The components of the Underlying Index are likely to change over time. As of October 31, 2025, the Underlying Index had 625 components. BFA uses an indexing approach to try to achieve the Funds investment objective. The Fund does not try to beat the index it tracks and does not seek temporary defensive positions when markets decline or appear overvalued. Indexing may eliminate the chance that the Fund will substantially outperform the Underlying Index but also may reduce some of the risks of active management, such as poor security selection. Indexing seeks to achieve lower costs and better after-tax performance by aiming to keep portfolio turnover low in comparison to actively managed investment companies. BFA uses a representative sampling indexing strategy to manage the Fund. Representative sampling is an indexing strategy that involves investing in a representative sample of securities or other instruments that collectively has an investment profile similar to that of an applicable underlying index. The instruments selected are expected to have, in the aggregate, investment characteristics (based on factors such as market value and industry weightings), fundamental characteristics (such as return variability, duration ( i.e. , an instrument's price sensitivity to a change in interest rates), maturity or credit ratings and yield) and liquidity measures similar to those of an applicable underlying index. The Fund may or may not hold all of the components of the Underlying Index. The Fund will invest at least 80% of its assets in the component securities of the Underlying Index, and the Fund will invest at least 90% of its assets in fixed income securities of the types included in the Underlying Index that BFA believes will help the Fund track the Underlying Index. The Fund will invest no more than 10% of its assets in futures, options, and swaps contracts that BFA believes will help the Fund track the Underlying Index as well as in fixed income securities other than the types included in the Underlying Index, but which BFA believes will help the Fund track the Underlying Index. Cash and cash equivalent investments associated with a derivative position will be treated as part of that position for the purposes of calculating the percentage of investments included in the Underlying Index. The Fund seeks to track the investment results of the Underlying Index before fees and expenses of the Fund. The Fund may lend securities representing up to one-third of the value of the Fund's total assets (including the value of any collateral received). The Underlying Index is sponsored by Bloomberg, MSCI Solutions, or their affiliates, which are ? independent of the Fund and BFA. The Index Provider determines the composition and relative weightings of the components of the Underlying Index and publishes information regarding the market value of the Underlying Index. Industry Concentration Policy. The Fund will concentrate its investments ( i.e. , hold 25% or more of its total assets) in a particular industry or group of industries to approximately the same extent that the Underlying Index is concentrated. For purposes of this limitation, securities of the U.S. government (including its agencies and instrumentalities), repurchase agreements collateralized by U.S. government securities, and securities of state or municipal governments and their political subdivisions are not considered to be issued by members of any industry. Show less