Compared to the Spheres, Which of the Following Has "The

question 141

Multiple Choice

Compared to the spheres, which of the following has "the hardest boundaries to pin down"?

• A) atmosphere
• B) biosphere
• C) lithosphere
• D) hydrosphere
• E) All of the above: they are equally imprecise.

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Definitions:

Fossil Record

The total number of fossils that have been discovered, as well as the information derived from them, providing evidence about the history of life on Earth.

Interbred

The result of breeding or mating between closely related individuals, often leading to a reduction in genetic diversity and potential health issues.

Vertebrate Groups

Categories of animals with backbones, including mammals, birds, reptiles, amphibians, and fish.