<span>The following statements explain how oxygen was introduced into the earliest atmosphere of the Earth and how the presence of oxygen affected life on Earth.
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B) Oxygen is needed to carry out many life processes. The addition of oxygen to the earth's atmosphere assisted with the development of eukaryotic organisms.
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D) Photosynthesis was carried out as cyanobacteria evolved. Oxygen is a product of photosynthesis.
They have a spine
hope it helps
Can you reright it in English?