The Global Sustainability Fixed Income Portfolio invests in a broad portfolio of investment grade debt securities (e.g., rated AAA to BBB- by S&P Global Ratings (“S&P”) or Fitch Ratings Ltd. (“Fitch”) or Aaa to Baa3 by Moody’s Investor’s Service, Inc. (“Moody’s”)) of U.S. and non-U.S. corporate and government issuers, while excluding or underweighting securities of corporate and certain non-sovereign government issuers based upon the Portfolio’s sustainability impact considerations. At times, the Portfolio may invest a majority of its net assets in securities of U.S. and non-U.S. government issuers. The Advisor expects that the Portfolio will primarily invest in the obligations of issuers that are in developed countries. The Advisor selects the Portfolio's foreign country and currency

compositions based on an evaluation of various factors, including, but not limited to, relative interest rates and exchange rates.

The Global Sustainability Fixed Income Portfolio will be managed with a view to capturing expected credit premiums and expected term premiums. The term “expected credit premium” means the expected incremental return on investment for holding obligations considered to have greater credit risk than direct obligations of the U.S. Treasury, and “expected term premium” means the expected relative return on investment for holding securities having longer-term maturities as compared to shorter-term maturities. In managing the Portfolio, the Advisor will increase or decrease investment exposure to intermediate-term securities depending on the expected term premium and also increase or decrease investment exposure to non-government securities depending on the expected credit premium. Under normal circumstances, the Portfolio will generally maintain a weighted average duration of no more than one half year greater than, and no less than one year below, the weighted average duration of the Bloomberg Global Aggregate Bond Index (Hedged to USD), which was approximately 6.70 years as of December 31, 2023. From time to time, the Portfolio may deviate from this duration range when the Advisor determines it to be appropriate under the circumstances. Duration is a measure of the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates.

The Global Sustainability Fixed Income Portfolio intends to invest its assets to gain exposure to at least three different countries, including the United States. Under normal circumstances, the Portfolio invests at least 30% of its net assets in non-U.S. issuers. As of the date of the Prospectus, the Portfolio invests approximately 45% of its net assets in U.S. issuers. This percentage will change due to market conditions. An issuer may be considered to be of a country if it is organized under the laws of, maintains its principal place of business in, has at least 50% of its assets or derives at least 50% of its operating income in, or is a government, government agency, instrumentality or central bank of, that country. As a non-fundamental policy, under normal circumstances, at least 80% of the Portfolio’s net assets will be invested in fixed income securities considered to be investment grade quality. The Portfolio may invest in obligations issued or guaranteed by the U.S. and foreign governments, their agencies and instrumentalities, bank obligations, commercial paper, repurchase agreements, money market funds, obligations of other domestic and foreign issuers, securities of domestic or foreign issuers denominated in U.S. dollars but not trading in the United States, and obligations of supranational organizations. In addition, the Portfolio is authorized to invest more than 25% of its total assets in U.S. Treasury bonds, bills and notes, and obligations of federal agencies and its instrumentalities.

The Global Sustainability Fixed Income Portfolio’s investments may include foreign securities denominated in foreign currencies. The Portfolio intends to hedge foreign currency exposure to attempt to protect against uncertainty in the level of future foreign currency rates. The Portfolio may enter into foreign currency forward contracts to hedge against fluctuations in currency exchange rates or to transfer balances from one currency to another. The Portfolio also may enter into credit default swaps on issuers or indices to buy or sell credit protection to hedge its credit exposure; gain market or issuer exposure without owning the underlying securities; or increase the Portfolio’s total return. The Portfolio also may use derivatives, such as futures contracts and options on futures contracts, for hedging purposes such as hedging its interest rate or currency exposure or for non-hedging purposes as a substitute for direct investment or to increase or decrease market exposure based on actual or expected cash inflows to or outflows from the Portfolio.

The Global Sustainability Fixed Income Portfolio may lend its portfolio securities to generate additional income.

The Advisor intends to take into account the impact that companies may have on the environment and other sustainability considerations when making investment decisions for the Global Sustainability Fixed Income Portfolio. Relative to a portfolio without these considerations, the Portfolio will exclude or underweight securities of companies that, according to the Portfolio’s sustainability impact considerations, may be less sustainable as compared either to other companies with securities in the Portfolio’s investment universe or other companies with similar business lines. Similarly, relative to a portfolio without sustainability impact considerations, the Portfolio will overweight securities of companies that, according to the Portfolio’s sustainability impact considerations, may be more sustainable as compared either to other companies with securities in the Portfolio’s investment universe or other companies with similar business lines. In considering sustainability impact and other factors that the Advisor believes may be important to investors, the Advisor will consider greenhouse gas emissions intensity, fossil fuel reserves, coal, land use, water use, factory farming activities, biodiversity, involvement in toxic spills or releases, operational waste, tobacco, palm oil, cluster munitions manufacturing, landmine manufacturing, civilian firearms manufacturing, the ownership or operation of private prisons and/or immigrant detention facilities, child labor, and

severe environmental, social, or governance controversies that indicate operations inconsistent with responsible business conduct standards (such as those defined by the UN Global Compact Principles and the OECD Guidelines for Multinational Enterprises), among other factors. In particular, the Portfolio will exclude securities of companies the Advisor considers to have high greenhouse gas emissions intensity or fossil fuel reserves relative to other issuers. The Advisor may engage third party service providers to provide research and/or ratings information relating to the Portfolio’s sustainability impact considerations with respect to securities in the Portfolio, where information is available from such providers. In addition to excluding or underweighting securities of corporate issuers based upon the Portfolio’s sustainability impact considerations, the Portfolio also will exclude or underweight securities of supranational organizations and certain non-sovereign governmental agencies (both U.S. and non-U.S.) that may be less sustainable as compared to other similar issuers, based upon the Portfolio’s sustainability impact considerations. The Portfolio’s investments in securities of U.S. and non-U.S. sovereign issuers are not subject to the sustainability impact considerations identified above. The Advisor, however, considers securities issued by the U.S. Treasury and certain U.S. agencies and instrumentalities that are not subject to the sustainability impact considerations identified above to be consistent with the Portfolio’s strategy of investing in sustainable investments.

The Portfolio may periodically modify, add, or remove certain sustainability impact considerations. (See “Additional Information on Investment Objectives and Policies—Applying the Portfolios’ Sustainability Impact Considerations” in this Prospectus.)