Classes of ESG-oriented fixed income debt issuance include:

The inclusion of "All of the above" as the correct choice highlights that there are various classes of ESG-oriented fixed income debt issuance that cater to different environmental and social objectives.

Green bonds are specifically created to fund projects that have positive environmental impacts, such as renewable energy, energy efficiency, and sustainable waste management. These bonds are a well-established part of the fixed income market focused on sustainability.

Blue bonds, on the other hand, are designed to finance projects related to ocean and water sustainability. They are a more recent innovation within the green finance space, addressing the critical importance of protecting marine resources and investments that contribute to sustainable fishing, coral reef restoration, and clean water initiatives.

Green collateralized loan obligations (CLOs) demonstrate the integration of ESG criteria into structured finance. These instruments pool together loans made to borrowers that have specific green or environmentally sustainable characteristics, thus providing investors a way to put their money toward environmentally responsible companies.

The acknowledgment of all these options showcases the diversity and innovation within the ESG debt market, indicating a growing recognition of the various environmental issues that can be targeted through fixed income investments. This multifaceted approach enables a range of investors to align their portfolios with their sustainability values while still participating in fixed income market returns.