The correct answer is number two
The atmosphere and Earth's interior are layered by density. Gravity pulls more strongly on denser materials so denser materials are at the center of things. Earth's core, at its center, is denser than its crust.
Answer:
There is overwhelming evidence that human activities, especially burning fossil fuels, are leading to increased levels of carbon dioxide and other greenhouse gases in the atmosphere, which in turn amplify the natural greenhouse effect, causing the temperature of the Earth's atmosphere, ocean.