B. specific to a substrate
For many of their illnesses scientist and doctors haven't treated them before so they don't know how to treat them or exactly if the animal can handle the treatment
They are the same in that most of the reproductive organs of both sexes develop from similar embryonic tissue, meaning they are homologous. Both systems have gonads (male have testes and female have ovaries) that produce gametes (testes produce sperm and ovaries produce egg or ovum) and sex organs.
Answer:
B
Explanation:
B is referring to cell theory, which basically states that all living things are made of cells and all cells come from other cells withe the exception of the first life forms.