C. The cell took in another ancient prokaryotic cell, which began living inside it.
I, seems to be the answer, because its not a sexual reproduction, (this occurs in cells, its not sexual reproduction, you would need the egg and sperm.
Oxygen is an abiotic factor that is beneficial by-product of primary production.
<u>Explanation:</u>
The non living parts of an ecosystem that mainly affects the living organisms in it are called as an abiotic factor. These can include soil, temperature, water, oxygen and sunlight. The major energy source in earth is Oxygen which is abiotic factor.
It is very essential for the photosynthesis process to take place. Here, the plants converts water and carbon dioxide into oxygen and sugar. This becomes food for plants. Then these plants are eaten by animals. Thus oxygen is an important and beneficial by-product of photosynthesis. Oxygen is also very important for the survival of human beings.
