Explanation:

- CITES stands for the Convention on International Trade in Endangered Species of Wild Fauna and Flora.

- It is a treaty to protect endangered plants and animals.

- The aim of CITES is to ensure that international trade does not threaten the survival of species.

- CITES regulates the trade of specimens of wild animals and plants, ensuring sustainability.

- "E" in CITES stands for "Endangered."

- Option 1: Endangered - This option is correct as it aligns with the purpose of CITES.

- Option 2: Environmental - Not correct, though related, it doesn't fit the acronym.

- Option 3: Eco-friendly - Incorrect as it doesn't relate to the specific focus of species.

- Option 4: Evolutionary - Wrong because it's unrelated to the trade and protection context.

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