The obvious answer is a bc it does not use and toxic fuels
1. Early earth had no ozone layer, which means it was most likely extremely hot.
2. Young earth had no oxygen and life needs oxygen in order to survive.
3. There where so many natural disasters happening all the time, like volcanic eruptions and constant impact with meteorites and asteroids.
-Extra one (4. Earth originally had no ocean and water. Oceans eventually formed from the water vapor released from the volcanic eruptions, but before that there was nothing.)
A.
Animal scientists applies principles of the biological, physical, and social sciences to the problems associated with livestock production and management.
Answer:
Both contain genetic material, in the form of DNA and/or RNA. Both of them can replicate, that is, produce more organisms similar to themselves. ... They require a host cell to carry out life processes, such as replication and carrying out genetic instructions, etc. Bacteria are relatively bigger in size than viruses.