Which federal law, signed in 1973, protects species determined to be threatened or endangered and has been credited with saving the bald eagle, the grizzly bear, and the whooping crane?

• A Migratory Bird Treaty Act
• B Marine Mammal Protection Act
• C Wilderness Act
• D Endangered Species Act ✓

The Endangered Species Act is one of the world's strongest wildlife protection laws, requiring federal agencies to ensure their actions do not jeopardise listed species.