What is the name of the UK law that supports principles of sustainability related to the environment?

The Environment Act 2021 is the correct answer as it represents a comprehensive framework aimed at addressing environmental issues and promoting sustainability in the UK. This Act consolidates a wide range of measures to improve air and water quality, enhance biodiversity, and tackle waste management, thus aligning with broader sustainability principles. It establishes new environmental governance structures, including the Office for Environmental Protection, which holds the government accountable for its environmental performance, and it sets legally binding targets for various environmental metrics.

The other options, while significant in their own rights, do not encompass the same breadth of sustainability principles as the Environment Act 2021 does. The Climate Change Act 2008 primarily focuses on reducing greenhouse gas emissions, while the Environmental Protection Act 1990 addresses pollution and waste but does not specifically set out sustainability goals. The UK Sustainability Act 2015 is less known and does not carry the same legislative weight as the Environment Act 2021 in terms of broad environmental policy and sustainability objectives.