Answer:
evolution of life on Earth
Explanation:
Life began on Earth at least 3.5 to 4 billion years ago, and it has been evolving ever since. At first, all living things on Earth were simple, single-celled organisms. Much later, the first multicellular organisms evolved, and after that, Earth's biodiversity greatly increased.
Answer:
it increases oxygen levels and decrease carbon dioxide levels
The answer for this one is b) Looping of DNA
Answer: Pollution, climate change, habitat loss, or invasive species
